Biology Final Exam

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Which of the following is NOT a characteristic of all life as we know it on Earth?

- ability for sexual reproduction
- having mitochondria

Families are divided into as the next taxonomic level.

genera

An organism is a eukaryote will no cell walls. It could belong to which of the following kingdoms?

protista and animalia

An organism is a multicellular eukaryote with cells organized into tissues but with no cell walls. It could belong to which of the following kingdoms?

animalia

Organisms that obtain energy by breaking down waste products and dead bodies of other organisms are most specifically called:

decomposers

What is our species name?

Homo sapiens

When there is a pH change from pH 2 to pH 4 this means that

the amount of [H+] is 100x less than before and
the amount of [OH-] is 100x more than before

Select below each property of water that is primarily due to hydrogen bonding.

- ice floats on liquid water
- nonionic polar substances tend to dissolve in water
- water moderates temperature more than most substances
- water exhibits highly cohesive behavior

Which of the following are considered carbohydrates?

- glucose
- cellulose
- chitin
- glycogen
- starch
- sucrose

Which of the following are considered lipids?

- steroid
- phospholipid
- cholesterol
- triacylglycerol

Which of the following is responsible for ?-pleated sheet structures in proteins?

hydrogen bonds involving atoms of the polypeptide backbone

Which of the following represent correct RNA-RNA basepairing rules?

C-G
A-U

Match each monomer type or component with the category of organic molecules to which it belongs.

- amino acid (protein)
- monosaccharide (carbohydrate)
- nucleotide (nucleic acid)
- fatty acid (lipid)

Match each bond type with the category of organic molecules to which it belongs or is commonly found.

- glycosidic (carbohydrate)
- peptide (protein)
- ester (lipid)
- phosphodiester (nucleic acid)

The substance N2 is held together by covalent bonds. Based on the definitions used in this course, which of the following is true?

N2 is a molecule but not a compound.

This organelle is a winding membrane network with both smooth and rough regions; in the rough regions proteins are inserted into the lumen of this organelle as the proteins are made.

endoplasmic reticulum (ER)

Which kingdom is characterized by its members being multicellular eukaryotes without cell walls?

animalia

Consider a spherical cell that begins with a radius of 2 �m. As it grows so that its radius becomes 4 �m, what will happen to its volume and its surface area?

volume will become 8x larger, while surface area will become 4x larger

If the pH of a solution changes from pH 4 to pH 8, it means that the

concentration of H+ is 1/10,000 of what it was at pH 4

The nucleolus is the site in a cell where:

ribosome subunits are made

This is a double-membraned organelle with its own DNA, with membraned sacks called thylakoids, and with an interior lumen called the stroma.

chloroplasts

About 25 of the 92 natural elements are known to be essential to life. Which four of these 25 elements make up approximately 96% of living matter?

carbon, hydrogen, nitrogen, oxygen

Consider the scientific name for the common fruit fly, Drosophila melanogaster. Which of the following is true?

Drosophila is the genus name and Drosophila melanogaster is the species name.

A molecule with the chemical formula C14H28O4 is probably a

lipid

Water has a molecular mass of 18g per mole, and glucose has a molecular mass of 180g per mole. Which of the following would have approximately one glucose molecule for every water molecule?

18g of water and 180g of glucose

Motor proteins provide for molecular motion in cells by interacting with what types of cellular structures?

microtubules

This organelle is a granular body that is the site of protein synthesis.

ribosome

The chemical linkages that occur when atoms share electrons equally are called

nonpolar covalent bonds

Cells of the liver are given radioactively labeled amino acids that they will incorporate into proteins. This "tagging" of newly synthesized proteins enables a researcher to track their location. In this case, we are tracking a digestive enzyme that stays

ER ? Golgi ? lysosome

In the fractionation of homogenized cells using centrifugation, the primary factor that determines whether a specific cellular component ends up in the supernatant or the pellet is

the size and weight of the component

Isotopes of the same element have:

the same number of electrons and the same atomic number but different atomic masses

According to the rules for normal basepairing, which of the following represents a correct DNA-DNA basepair?

C-G

Related classes are grouped into a/an ____ as the next taxonomic level.

phylum

What is the atomic mass of an atom with 8 protons, 9 neutrons, and 10 electrons?

17

This organelle has cis, medial, and trans regions and is a stack of flattened membrane-bound sacs called cisternae where proteins are processed, modified, and sorted.

golgi apparatus

Why does ice float in liquid water?

hydrogen bonds stabilize and keep the molecules of ice farther apart than the water molecules of liquid water.

Phosphodiester bonds are the typical bonds between:

nucleotides

Under which of the following conditions would you expect to find a cell with a predominance of free ribosomes (free meaning not bound to the ER)?

a cell that is producing cytoplasmic enzymes

A scientist wants to investigate the surface of bacterial cells. She decides to use 70,000x magnification. Which instrument would be best suited to that task?

a scanning electron microscope

When added to an aqueous solution at pH (7.0), an acid such as HCl will

act as a proton donor, lowering the pH of the aqueous solution

Cell theory states that:

on Earth today, new cells are only made from existing cells

Investigations of carbon dioxide (CO2) in the past have shown that the amount of CO2 found in a gas mixture is inversely correlated with the rate of cooling of that gas mixture - that is, when there is more CO2 present gas mixtures have been found to cool

I - inductive
II - deductive

What type of bond is a result of the attraction between a region with a partial positive charge (?+) and a region with a partial negative charge (?-)?

hydrogen

A cell has at least the following molecules and structures: enzymes, DNA, ribosomes, large central vacuole, cell wall, and plasma membrane. It could be a cell from

a bacterium only

Water is a very effective temperature buffer because of its

relatively high specific heat.

These proteins are imbedded in the plasma membrane of animal cells and typically receive signals from the extracellular matrix.

integrins

Which of the following is most likely to gain an electron and become an anion?

fluorine (7 valence electrons)

This double-membraned organelle is the site in eukaryotic cells of most of their ATP production via aerobic respiration; its highly folded inner membrane forms cristae.

mitochondrion

Microfilaments are _ than microtubules and are made of _ .

thinner; actin monomers

Based on our current model of cells, which of the following is true of life on Earth?

- today new cells are only made from existing cells
- all living organisms are composed of one or more cells

As a typical cell grows larger, which of the following occurs?

cell volume increases faster than surface area

After a solution containing lysed cells is subjected to relatively low-speed centrifugation:

the lightest cell components will be found in the supernatant

A cell has at least the following molecules and structures: enzymes, DNA, ribosomes, plasma membrane, endoplamsmic reticulum (ER), and mitochondria. It could be a cell from

a plant or an animal

What is the function of the nuclear pores in living eukaryotic cells?

regulation of passage of materials into and out of the nucleus

Match the organelle or cellular region with a description of its structure and/or function.

- nucleolus: synthesis of rRNA
- smooth endoplasmic reticulum: synthesis of lipids
- rough endoplasmic reticulum: attachment site for ribosomes
- ribosomes: protein synthesis
- golgi apparatus: cisternae where proteins are modified, sorted, and sent off t

These organelles have their own DNA, ribosomes, and reproduction within the cell, which is explained by the endosymbiont theory that holds that these organelles were once free-living bacterial cells that came to reside in ancient eukaryotic cells.

- mitochondria
- chloroplasts

Flagella and cilia bend or move, imparting mobility to cells. How do these structures move?

Dynein is a motor protein that uses ATP and is responsible for movement of cilia and flagella.

Small molecules can travel directly from the cytoplasm of one cell to the cytoplasm of an adjacent cell through

- plasmodesmata
- gap junctions

Which of the following could describe a process that allows protons (H+) to move against their concentration gradient across a biological membrane using a protein channel?

active transport

Which of these substances is likely to cross a cellular membrane by simple diffusion?

- O2
- H2O
- N2
- CO2

Which of these are associated with membranes but are not embedded in the lipid bilayer at all?

peripheral proteins

Select all of the TRUE statements about membrane phospholipids, assuming that the fluid mosaic model of cell membranes is true.

- they rarely flip from one side of the membrane to the other
- they often move laterally along the plane of the membrane

Which of the following terms describes where an inhibitor could bind to an enzyme?

- allosteric site
- active site

Consider a situation in which an enzyme is operating at optimum temperature and pH, and has been saturated with substrate. Which of the following things could you to do to significantly increase the rate of the reaction?

add more enzyme

When Zn+2 is introduced to a solution containing a specific enzyme the rate of the reaction catalyzed by that enzyme dramatically increases. Further studies reveal that the enzyme does not function as a catalyst at all if Zn+2 is absent, and that Zn+2 ass

a cofactor

Which of the following mechanisms do enzymes use to reduce activation energy requirements and thus speed up a reaction?

- holding reactants close together in the right orientation for the reaction
- putting a strain on existing bonds
- providing a microenvironment that is more chemically suited to the reaction
- direct involvement in the reaction during transition states

When ATP hydrolysis is used in a coupled reaction to provide energy:

- a phosphorylated intermediate is often produced
- the overall reaction has a net exergonic nature

Select all of the TRUE statements.

- exergonic reactions are spontaneous
- exergonic reactions have a net release of energy
- endergonic reactions are not spontaneous
- endergonic reactions have a net requirement for energy

Select all of the statements that are TRUE statements according to the first and second laws of thermodynamics.

- energy can be transferred or change forms
- living things must increase the net entropy of their surroundings
- every energy transfer increases the entropy of the universe

Which of the following terms describes where substrate(s) binds to an enzyme?

active site

CO2 is released during which stage(s) of aerobic respiration?

- oxidation of pyruvate to acetyl CoA
- the citric acid cycle

Considering only glycolysis, the oxidation of pyruvate molecules to acetyl-CoA molecules, and the citric acid cycle, how many net NADH molecules will be produced using one glucose molecule as an energy source? (This means that you are NOT including oxidat

10

Cytochromes, iron-sulfur proteins, and ubiquinone are all part of:

an electron transport chain

The function of both alcohol fermentation and lactic acid fermentation is to

regenerate NAD+

How many molecules of NADH would be produced by three turns of the citric acid cycle?

9

Which of the following statements are true given the reaction below?
C6H12O6 + 6O2 --> 6CO2 + 6H2O + energy

- C6H12O6 gets oxidized
- compared to O2, H2O is reduced
- O2 gets reduced

During glycolysis, when glucose is catabolized to pyruvate, most of the energy of glucose is

retained in the pyruvate

In chemiosmosis, ATP is produced as hydrogen ions (protons) pass through

ATP synthase

After glycolysis, for each molecule of glucose catabolized there are a net

2 pyruvates, 2 ATP, and 2 NADH produced

Acetyl CoA enters the citric acid cycle by

reacting with oxaloacetate, forming citrate and freeing CoA

Where is the electron transport chain used in oxidative phosphorylation found in eukaryotic cells?

mitochondrial inner membrane

The ultimate electron acceptor in oxidative phosphorylation is:

O2

During the citric acid cycle, each acetyl group entering the cycle yields:

1 ATP, 3 NADH, and 1 FADH2

As NADH and FADH2 are oxidized, the energy released during electron transport is used in part to

pump protons across a membrane against their concentration gradient

When a triacylglycerol fat is used as an energy source, glycerol is converted to a compound that enters aerobic respiration

in glycolysis

In the RuBP regeneration phase of the Calvin cycle (C3 cycle), the production of 6 RuBP molecules requires _ G3P molecules and the use of _ ATPs and _ NADPHs.

10; 6; 0

Rank these types of electromagnetic radiation, from least energetic to most energetic.

radio waves < infrared light < red light < green light < blue light < ultraviolet (UV) light < X-rays < gamma rays

Energy captured from light for photosynthesis is brought into the Calvin cycle (C3 cycle) via

- ATP
- NADPH

In a photosynthetic plant cell, where are ATP synthase complexes located?

- inner mitochondrial membrane
- thylakoid membrane

Assume that an electron travels through linear electron flow in photosynthesis, all the way from water to NADPH. Place these items in the order that the electron will pass through on its journey, starting from when it is removed from water.

Photosystem II (P680) < plastoquinone (Pq) < plastocyanin (Pc) < Photosystem I (P700) < ferredoxin

A family is divided into related ____ as the next taxonomic level.

genera

All of the following are correct matches of the location of a protein and the location of its synthesis except

lysosomal proteins in free cytoplasmic ribosomes

These organelles have their own ribosomes and their own "cell" division, which is explained by the endosymbiont theory that holds that these organelles were once free-living bacterial cells that came to reside in ancient eukaryotic cells.

- mitochondria
- plastids

Which of the following is responsible for ?-helix structures in proteins?

hydrogen bonds involving atoms of the polypeptide backbone

Cell theory states that

on earth today, new cells are only made from existing cells

Consider the scientific name for the common house mouse, Mus musculus. Which of the following is true?

Mus is the genus name and Mus musculus is the species name.

Insulin is secreted as a free protein (not membrane-bound) by certain cells of the mammalian pancreas. Insulin must:

be inserted into the ER lumen as it is made, then pass through the Golgi apparatus before secretion

In studies of species of mammals that live in colder climates (such as the Arctic), it has been consistently found that ancestors and the closest living relatives of those species that lived or live in warmer climates have a lower average adult body mass

I - deductive
II - inductive

Which of the following is most likely to lose an electron and become a cation?

sodium (1 valence electron)

A molecule with the chemical formula C18H32O16 is probably a

carbohydrate

If the pH of a solution changes from pH 6 to pH 3, it means that the

concentration of H+ is 1000 times greater than what it was at pH 6

This organelle has cis, medial, and trans regions and is a stack of flattened membrane-bound sacs called cisternae where proteins are processed, modified, and sorted

golgi apparatus

Which structure is the site of the synthesis of proteins that may be exported from the cell?

rough ER

The substance KI is held together by ionic bonds. Based on the definitions used in this course, which of the following is true?

it is a compound but not a molecule

A cell has at least the following molecules and structures: enzymes, DNA, ribosomes, and plasma membrane. It could be a cell from

a plant or an animal

Proteins leave the ER in small membrane-bound sacs called:

vesicles

This protein is the main structural protein in the extracellular matrix of animals

collagen

What type of bond produces a region with a partial positive charge (?+) and a region with a partial negative charge (?-)?

polar covalent

A carbon atom with an atomic mass 14 and atomic number 6 has

8 neutrons and 6 protons

Microfilaments are _______ than microtubules and are made of _______

thinner; actin monomers

In the formation of some lipids, condensation forms ___ linkages between glycerol and fatty acids

ester

A scientist wants to investigate the interior of bacterial cells. She decides to use 70,000x magnification, and will use very thin slices of the cell samples embedded in plastic resin. Which instrument would be best suited for her studies?

a transmission electron microscope

Chemical reactions and energy transformations in cells make up

metabolism

About 96% of living matter is made up of which four elements?

carbon, hydrogen, nitrogen, oxygen

The nucleolus is the site in a cell where

ribosome subunits are made

Which kingdom is characterized by its members being eukaryotes with chitin as the main structural component of their cell walls?

fungi

Water's high specific heat is mainly a consequence of the

absorption and release of heat when hydrogen bonds form and break

Besides explaining existing observations, the key characteristic of a model generated using the scientific method is that the model (be it a hypothesis, theory, principle, or law) is

testable, and thus able to be disproved if its predictions fail

The chemical linkages where atoms share electrons equally are called

nonpolar covalent bonds

During which phase of the cell cycle in eukaryotes is there a checkpoint that determines whether or not the cell is ready to duplicate its DNA and commit to starting the process that will lead to cell division?

G1

In eukaryotes the replication of chromosomal DNA occurs during

S phase

Which of the following lists eukaryotic cell cycle phases in a correct chronological order?

anaphase, telophase, interphase, prophase, metaphase

Typical human cells, if normal, have ______ chromosomes during anaphase.

92

Which of the following processes typically occur during prophase of mitosis in animal cells?

- nucleoli disintegrate
- nuclear membrane divides into many small vesicles
- a system of microtubules organizes between the two poles of the cell
- kinetochore microtubules connect to chromosome kinetochores
- chromatin of the chromosomes condenses

In which of the following should you find the chromosomes all lined up along the midplane of the cell, with sister chromatids for each chromosome having their kinetochores on opposite sides

metaphase

Suppose that a cell has 20 chromatids at prophase of mitosis. After mitosis and cytokinesis end, the two resulting daughter cells should have how many chromosomes each?

10

Cytokinesis in animal cells involves:

- formation of a cleavage furrow
- contraction of a ring of actin microfilaments

Typical human cells, if normal, have ______ chromosomes during anaphase I.

46

Which of the following processes typically occur during prophase I of meiosis in animal cells?

- homologous chromosomes pair up
- nucleoli disintegrate
- nuclear membrane divides into many small vesicles
- a system of microtubules organizes between the two poles of the cell
- kinetochore microtubules connect to chromosome kinetochores
- crossing ov

Suppose that a cell has 20 chromatids at G1 and winds up going through meiosis. After meiosis ends, each of the four resulting cells should have how many chromosomes each?

10

In which of the following phases of meiosis should your find sister chromatids attached to each other with their kinetochores on opposite sides?

- prophase II
- metaphase II

Which of the following best matches the life cycle known as sporic meiosis (or alternation of generations), which is found in plants and is also common in algae as well as many other organisms?

zygote ? mitosis ? meiosis ? mitosis ? production of gametes ? fertilization

The concept that sex allows populations to store genetic diversity to provide an advantage in the face of ever-changing environmental constraints, such as to deal with constantly evolving parasites, is the _______ hypothesis.

Red Queen

How do the two members of a pair of homologous chromosomes typically differ from each other?

the precise sequence of the DNA within each of the chromosomes

Which of the following typically occurs during anaphase I of meiosis?

- sister chromatids travel together
- homologous chromosomes segregate

In most cases, an animal with a diploid number of 2n = 24 chromosomes will have _ chromosomes in its gametes and _ chromosomes in its somatic (body) cells.

12; 24

In roses assume that red or yellow flower color is controlled by a single gene with two alleles. Crossing roses with yellow flowers with each other yields only offspring that produce yellow flowers, but when you cross roses with red flowers with each othe

3/4 red, 1/4 yellow

In peas, the allele for tall (T) is dominant over short (t), and the unlinked gene for seed color has the allele for yellow seeds (G) dominant over green seeds (g). What is the predicted phenotypic ratio for offspring from this cross: Ttgg x TtGg

3 tall, yellow: 3 tall, green: 1 short, yellow: 1 short, green

In peas, the allele for tall (T) is dominant over short (t), and the unlinked gene for seed color has the allele for yellow seeds (G) dominant over green seeds (g). What is the predicted phenotypic ratio for offspring from this cross: TtGg x TtGg

9 tall, yellow: 3 tall, green: 3 short, yellow: 1 short, green

In peas, the allele for tall (T) is dominant over short (t), and the unlinked gene for seed color has the allele for yellow seeds (G) dominant over green seeds (g). What is the predicted phenotypic ratio for offspring from this cross: Ttgg x ttGG

1 tall, yellow: 1 short, yellow

One gene determines red vs. white flowers in pea plants, and another determines axial vs. terminal flowers. Two true-breeding stocks of pea plants are crossed. One parent has red, axial flowers and the other has white, terminal flowers; all F1 individuals

3/16

In humans, one form of polydactyly (extra fingers and toes) is controlled by a single autosomal gene with two possible alleles; the dominant allele leads to polydactyly, the recessive is for the normal number of fingers and toes. A woman with this form of

0.25

In humans, the gene for cystic fibrosis is linked to a gene for a rare form of "blue/yellow" colorblindness. Both of these are recessive. In a study of a small population, several matings were recorded between individuals heterozygous for both genes and i

16

In cats, black fur color is caused by an X-linked allele; the other allele at this locus causes orange color. The heterozygote is tortoiseshell. What kinds of offspring would you expect from the cross of a black female and an orange male?

tortoiseshell females; black males

A woman is red-green colorblind, and she mates with a man who has normal color vision. Knowing that red-green colorblindness is controlled by a gene on the X chromosome, what can you predict for their children with regard to inheritance of color vision?

all of the boys and none of the girls will be colorblind

A woman with normal color vision, but whose father is red-green colorblind, mates with a man who is red-green colorblind. Knowing that red-green colorblindness is controlled by a gene on the X chromosome, what can you predict for their children with regar

half of the boys and half of the girls will be colorblind

Recall that the gene for red or white eye color in fruit flies is X-linked, with the white color allele recessive. You examine a vial of 100 flies that are all offspring from a single genetic cross. In the vial you find that all females are red-eyed, whil

XRXr ; XRY

In snapdragons, heterozygotes have pink flowers, whereas homozygotes have either red or white flowers. When a pink-flowered snapdragon is crossed with a red-flowered snapdragon, what proportion of the offspring will have white flowers?

0

A man and a woman each have a parent with type O blood. He has type A blood, and she has type B blood. If this man and woman have children, what is the predicted phenotype ratio for their offspring with respect to blood type?

1/4 A: 1/4 B: 1/4 AB: 1/4 O

In a rodent species from an island in the south Atlantic there are three different coat colors found in the population. Studies show that two genes (each with two alleles) determine the coat color in this species, and a dihybrid cross produces offspring w

epistasis

When columbines with lavender flowers are mated they produce offspring that make either dark purple, lavender, or white flowers. The ratio is 1 dark purple: 2 lavender: 1 white. This is an example of what kind of non-Mendelian inheritance pattern?

codominance or incomplete dominance

Substitution of one base pair for another in a coding region of a gene can result in a ____________ mutation where the changed codon still codes for the same amino acid as the original codon did.

silent

Small ribonucleoprotein particles (snRNPs, or "snurps") are involved in ________.

mRNA splicing

The central dogma describes the flow of information of gene expression as

DNA ? RNA ? protein

In the Hershey and Chase experiment, the pellet was radioactive after bacteria had been infected with 32P-labeled viruses and centrifuged. Why?

Bacteria were centrifuged to form the pellet, and they had incorporated radioactive DNA

Which of the following nucleotide sequences represents the complementary sequence that would bind to the DNA strand 5' - TCATGG - 3'?

3' - AGTACC - 5'

During DNA replication, the _ strand is assembled in the _ direction that the DNA double helix unwinds and is produced by _ replication.

lagging; opposite; discontinuous

Stopping transcription in eukaryotes requires:

generation of a poly-A tail

As a ribosome translocates along an mRNA molecule by one codon, which of the following occurs?

The tRNA that was in the A site moves into the P site.

RNA polymerase moves along the template strand of DNA in the _ direction of the template strand, and adds nucleotides to the _ end of the growing transcript.

3' to 5'; 3'

The DNA of an organism is studied and found to contain 36% cytosine. This organism should have _ % guanine and _ % adenine in its DNA.

36; 14

The process of adding the correct amino acid onto a tRNA molecule is catalyzed by ________.

an aminoacyl-tRNA synthetase

Which of the following represents an idea that Darwin learned from the writings of Thomas Malthus?

Populations tend to increase at a faster rate than their food supply normally allows.

The first public presentation of Charles Darwin's theory of evolution by means of natural selection was done jointly with a presentation of the work of ___ , who independently derived essentially the same theory.

Wallace

It has been observed that organisms on islands are different from, but closely related to, similar forms found on the nearest continent. This is taken as evidence that

island forms and mainland forms descended from common ancestors

Which is of the following are commonly used to date fossils (especially those likely to be millions of years old)?

- their association with index fossils
- their relative position in rock layers
- radioisotope dating of rock layers above and below the fossils

Natural selection is based on which of the following?

- populations tend to produce more individuals than the environment can support
- genetic variation exists within populations
- individuals who survive longer tend to produce more offspring than those who die young
- the best-adapted individuals tend to p

Which of the following are part of Darwin's mechanism of evolution?

- competition among organisms
- differential reproductive success
- overproduction of offspring
- genetic variation among individuals

The modern theory of plate tectonics is used in studies of

biogeography

Which of the following pieces of evidence most strongly supports the common origin of all life on Earth?

all organisms use essentially the same genetic code

Over evolutionary time, many cave-dwelling organisms have lost their eyes. Tapeworms have lost their digestive systems. Whales have lost their hind limbs. How can natural selection account for these losses?

Under particular circumstances that persisted for long periods, each of these structures presented greater costs than benefits

Which of the following types of electromagnetic radiation has the least energy per photon?

infrared light

Phosphodiester bonds are the typical bonds between

nucleotides

When used as an energy source triacylglycerol fats will typically provide a cell with

more than twice as much energy per unit weight than glucose provides

The production of alcohol or lactate from pyruvate during _ occurs as a means of regenerating _ from _

fermentation; NAD+; NADH

The conversion of citrate to isocitrate is catalyzed by a specific enzyme. When oxaloacetate is introduced to a solution containing the enzyme and a saturating concentration of citrate the rate of the reaction decreases. Adding more citrate partially over

a competitive inhibitor

During which phase(s) of mitosis are chromosomes composed of two chromatids each?

prophase and metaphase

Which of the following is not a component of the electron transport chain used in oxidative phosphorylation?

ATP synthase

Which of the following statements describes the results of this reaction?
C6H12O6 + 6O2 --> 6CO2 + 6H2O + energy

C6H12O6 gets oxidized and O2 gets reduced

During which phase do homologous chromosomes pair and have crossing-over occur between them?

prophase I

In most cases, an animal with a diploid number of 2n = 46 chromosomes will have _ chromosomes in its somatic (body) cells and _ chromosomes in its gametes

46; 23

What is the ultimate electron acceptor in noncyclic electron transport in photosynthesis?

NADP+

In the carbon reduction phase of the C3 cycle, the production of 12 G3P molecules requires _ 3-PGA molecules and the use of _ ATPs and _ NADPHs

12; 12; 12

Consider a situation in which an enzyme is operating at optimum temperature and pH, and has been saturated with substrate. What is your best option for increasing the rate of the reaction?

add more enzyme

The site where a noncompetitive inhibitor binds to an enzyme is called a/an

allosteric site

A process that allows protons (H+) to move with their concentration gradient across a biological membrane using a protein channel would be best termed as

facilitated diffusion

Which of the following terms applies to any protein that is imbedded in the lipid bilayer of a cellular membrane?

integral protein

Which of the following types of cell-cell contacts act as selective pores for exchange of materials between adjacent plant cells?

plasmodesmata

Where do the enzymatic reactions of the C3 cycle (Calvin cycle) take place?

stroma of the chloroplast

Which of the following is least likely to cross a cellular membrane by simple diffusion?

C6H12O6

Which of the following is NOT considered one of the primary ways that enzymes reduce activation energy requirements?

providing a net input of energy to the reactants

A 12-carbon fatty acid is processed via beta oxidation into 6 acetyl-CoA molecules, each of which then enter into the citric acid cycle. How many molecules of NADH would be produced by these six turns of the citric acid cycle?

18

The molecule _ is reduced relative to _

NADPH; NADP+

Plastocyanin passes electrons directly to

photosystem I/P700

If a cell is placed in a solution that is isotonic relative to the cell's cytosol, the cell will

have no net exchange of water with the solution

The tertiary structure of a protein is the

unique three-dimensional shape of a fully folded polypeptide chain

The energy source that most directly drives ATP synthesis during chemiosmosis is

the flow of H+ ions with their gradient through ATP synthase

Suppose that a cell has 8 chromatids at prophase of mitosis. After mitosis and cytokinesis end, the two resulting daughter cells should have how many chromosomes each?

4

Pinocytosis:

is ingestion of small regions of dissolved materials by the cell

Phospholipids can spontaneously form bilayer structures in water because of their

amphipathic nature

An enzyme that joins two molecules with covalent bonds would be considered a/an

ligase

In C4 plants and CAM plants, the reaction that initially fixes CO2 into a four-carbon compound is catalyzed by the enzyme

PEP carboxylase

A membrane-bound protein changes its shape when it binds to a hormone molecule on the outer surface of the cell. After the shape change, the protein is able to bind with a second protein and change the shape of the second protein, which then stimulates ad

singal transduction

Which of the following is a reasonable explanation for why unsaturated fatty acids help keep any membrane more fluid (which is preferred at lower temperatures)?

The double bonds in unsaturated fatty acids form bends in the fatty acid tails, forcing adjacent phospholipids to be further apart than they would be with saturated fatty acids

Diffusion is the net movement of particles from an area of _ initial concentration to an area of _ initial concentration

high; low

Oxidative decarboxylation of 2 pyruvates at the pyruvate dehydrogenase complex yields

2 acetyl CoA + 2 CO2 + 2 NADH

In the"fluid mosaic model

proteins associated with a membrane move around on the same side of a lipid bilayer that acts as a two-dimensional fluid

When during the cell cycle do sister chromatids separate?

anaphase

In anaphase I of meiosis

homologous chromosomes separate from each other

All of the following occur during prophase of mitosis in animal cells except

the homologous chromosomes pair up

What type of bond results in a region with a partial positive charge (?+) and a region with a partial negative charge (?-)?

polar covalent

A typical reaction that is catalyzed by an enzyme in the human body occurs at a very slow rate without the enzyme. In the absence of an enzyme, what would generally be required to make any reaction happen at a faster rate?

raise the temperature significantly

Which of the following best fits the life cycle of most fungi, known as zygotic meiosis?

zygote ? meiosis ? mitosis ? production of gametes ? fertilization

The primary role of oxygen in cellular respiration is to

act as a the final acceptor for electrons in the electron transport chain

A 12-carbon fatty acid is processed via beta oxidation into 6 acetyl-CoA molecules, each of which then enter into the citric acid cycle. How many molecules of CO2 would be released by these six turns of the citric acid cycle?

12

When ATP hydrolysis is used in a coupled reaction to provide energy

a phosphorylated intermediate is often produced

Which of the following is most likely to cross a cellular membrane by simple diffusion?

O2

A cell with 2n = 46 chromosomes goes through mitosis and cytokinesis. The result is __ cells that each have __ chromosomes

2; 46

A cell with 2n = 46 chromosomes goes through meiosis, including two rounds of cytokinesis. The result is __ cells that each have __ chromosomes

4; 23

The main reason that a cell performs cellular (aerobic) respiration is to

produce ATP

In many animal cells a membrane protein uses energy from ATP to move sodium ions and potassium ions across the plasma membrane against their concentration gradients. This is a classic case of what?

active transport

The main reason that a plant performs photosynthesis is to

produce organic molecules using light energy and CO2

During anaphase of mitosis you should find chromosomes composed how many chromatids each?

1

Which of the following best fits the life cycle of most animals, known as gametic meiosis?

zygote ? mitosis ? meiosis ? production of gametes ? fertilization

The breakdown of one glucose molecule during glycolysis ends with energy in various molecules. Most of the energy at the end of glycolysis is found

in pyruvate

In a plant cell, where are the ATP synthase complexes located?

both thylakoid membrane and inner mitochondrial membrane

Sister chromatids separate in what stage of meiosis?

anaphase II

In prophase of mitosis you should find that sister chromatids

have their kinetochores on opposite sides

Feedback inhibition is typically ______ , with the inhibitor binding to ______ on the enzyme

noncompetitive; an allosteric site

If a cell is placed in a solution that is hypotonic relative to the cell's cytosol, the cell will

overall wind up taking water from the solution

Plasmodesmata in plant cells are most similar in function to which of the following structures in animal cells?

gap junctions

When Zn+2 is introduced to a solution containing a specific enzyme the rate of the reaction catalyzed by that enzyme dramatically increases. Further studies reveal that the enzyme does not function as a catalyst at all if Zn+2 is absent, and that Zn+2 ass

a cofactor

The movement of substances out of a cell via a vesicle fusing with the plasma membrane is

exocytosis

Induced fit" refers to the fact that an enzyme typically changes its shape when _____ binds to it

a substrate

The electrons lost by the Photosystem I/P700 reactive center are sent to ______ , where two are needed for generation of NADPH

ferredoxin

Consider a situation in which an enzyme is operating at optimum temperature and pH and has not been saturated with substrate. What is your best option for increasing the rate of the reaction?

add more subsrate

Energy captured from light for photosynthesis is brought into the C3 cycle via

ATP and NADPH

Which of the following types of electromagnetic radiation has the most energy per photon?

X-rays

One important regulation point in the aerobic respiration of mammals occurs in glycolysis at the site of the enzyme phosphofructokinase, which is

inhibited by high levels of ATP

The reaction in the C3 cycle that adds CO2 to ribulose bisphosphate, known as carbon fixation or CO2 uptake, is catalyzed by the enzyme

rubisco

A process that allows amino acids to move against their concentration gradient across a biological membrane using a protein channel would be best termed as

active transport

When living systems couple exergonic with endergonic reactions, the overall reaction has a net exergonic nature because

no energy conversion is 100% efficient

The ultimate electron acceptor in oxidative phosphorylation is

O2

Glucose diffuses slowly through artificial phospholipid bilayers. The cells lining the small intestine, however, rapidly move large quantities of glucose from the glucose-rich food into their glucose-poor cytoplasm. Using this information, which transport

facilitated diffusion

For each molecule of glucose produced during the carbon fixation reactions of photosynthesis, __ RuBP molecules, __ CO2 molecules, and __ G3P molecules are involved in steps of the C3 cycle.

6; 6; 12

An enzyme that catalyzes a redox reaction would be considered a/an

oxidoreductase

In eukaryotes the replication of chromosomal DNA in the nucleus occurs during

S phase

Suppose that a cell has 28 chromatids at the end of S phase. After mitosis and cytokinesis end, the two resulting daughter cells should have how many chromosomes each?

14

Homologous chromosomes separate in what stage of meiosis?

anaphase I

In chemiosmosis, ATP synthase produces ATP using the energy from

protons flowing with their concentration gradient through ATP synthase

Which of the following is considered one of the primary ways that enzymes reduce activation energy requirements?

providing a microenvironment that is more chemically suited to the reaction

The conversion of phosphoenolpyruvate (PEP) to chorismate is catalyzed by a specific enzyme. When tyrosine is introduced to a solution containing the enzyme and a saturating concentration of PEP the rate of the reaction decreases. Adding more PEP partiall

a competitive inhibitor

Phagocytosis:

is engulfment of large solid particles by the cell

The molecule _____ is reduced relative to _______

H2O; O2

Bates provided what is considered to be one of the most important early contributions to studies of evolution when he wrote a paper where he used natural selection to explain

mimicry

In pea plants purple flower color is dominant over white flower color. A pea plant that is heterozygous purple-flowered is crossed with another pea plant that is heterozygous purple-flowered. Which answer fits the predicted genotype(s) of their offspring

1 AA : 2 Aa : 1 aa

In humans, sickle cell anemia is an ______ genetic disorder

autosomal recessive

Which of the following nucleotide sequences represents the complementary sequence that would bind to the DNA strand 5' - CTGACG - 3'?

3' - GACTGC - 5'

The DNA of an organism is studied and found to contain 32% adenine. This organism should have __% thymine and __% guanine in its DNA

32; 18

Stopping transcription in prokaryotes requires

copying a terminator sequence in mRNA

When rabbits with brown fur color are mated they produce offspring that have either red, brown, or white fur. The ratio is 1 red: 2 brown: 1 white. Based on this, inheritance of this color gene is apparently an example of

incomplete dominance

In a small mustard plant species, gene mapping crosses are performed between the gene controlling whether flower petals are produced and the gene controlling whether pollen is produced. Making no petals is recessive, as is making no pollen. For the cross

22 map units

A woman with blood type O has a child with blood type O. Which of the following choices gives all of the possible blood types for the father?

A, B, or O

In peas, the allele for tall (T) is dominant over short (t), and the unlinked gene for seed color has the allele for yellow seeds (G) dominant over green seeds (g). What is the predicted phenotypic ratio for offspring from this cross: ttGg x ttGg

3 short, yellow: 1 short, green

You are genetic counselor, and a couple comes to you with concerns that if they have a child together it could have hemophilia. The man has X-linked hemophilia; the woman does not have it, but her father did. Which of the following would be the most corre

any child that they produce will have a 50% chance of having hemophilia

What is the predicted phenotype ratio for human children if their mother's genotype is IAIB for blood type and their father is IAio?

1/2 A: 1/4 AB: 1/4 B

Fossils are typically dated by

association with index fossils, relative position in rock layers, and radioisotope dating of rock layers above and below

In snapdragons, heterozygotes have pink flowers, whereas homozygotes have either red or white flowers. When a white-flowered snapdragon is crossed with a pink-flowered snapdragon, what proportion of the offspring would be predicted to have pink flowers?

50%

A woman with normal color vision and a man who is red-green colorblind produce a daughter who is red-green colorblind. Knowing that red-green colorblindness is controlled by a gene on the X chromosome, you can predict that the odds of being red-green colo

50% for sons, 50% for daughters

In peas, the allele for tall (T) is dominant over short (t), and the unlinked gene for seed color has the allele for yellow seeds (G) dominant over green seeds (g). What is the predicted phenotypic ratio for offspring from this cross: ttGg x TtGg

3 tall, yellow: 1 tall, green: 3 short, yellow: 1 short, green

The physical division between the fauna of Asia and Australia is known as

The Wallace Line

Substitution of one base pair for another in a coding region of a gene can result in a ____________ mutation that changes a codon that once coded for an amino acid to code for a stop codon.

nonsense

In humans, wet earwax is a dominant trait governed by normal Mendelian inheritance for a single autosomal gene with two possible alleles; the other trait, dry earwax, is recessive. A woman with dry earwax and a man with wet earwax have a son, and he has d

heterozygous

Which of the following represents the order of increasingly higher levels of organization of chromatin?

nucleosome, 30-nm chromatin fiber, looped domain

A diploid cell that is 2N = 6 undergoes all of mitosis, including all cell divisions. The result is

2 cells, with 6 chromosomes each

In humans, wet earwax is a dominant trait governed by normal Mendelian inheritance for a single autosomal gene with two possible alleles; the other trait, dry earwax, is recessive. A man with dry earwax has one child, and that child has wet earwax. What i

homozygous recessive

Which of the following acts in DNA replication to begin new strands?

primase

You are genetic counselor, and a couple comes to you with concerns that if they have another child together it could have cystic fibrosis. The man does not have cystic fibrosis, but his brother did. Genetic tests reveal that the man is homozygous for the

No child that they produce should wind up with cystic fibrosis, but each of their offspring will have a 50% chance of being a carrier.

The general flow of information in gene expression is

DNA ? RNA ? protein

This type of RNA is about 70-80 bases long, basepairing with itself to form a folded 3-dimensional structure. It is often linked directly to a specific amino acid

tRNA

One gene determines red vs. white flowers in pea plants, and another determines axial vs. terminal flowers. Two true-breeding stocks of pea plants are crossed. One parent has red, axial flowers and the other has white, terminal flowers; all F1 individuals

3/16

A fatty acid is processed via beta oxidation into 8 acetyl-CoA molecules, each of which then enter into the citric acid cycle. How many molecules of CO2 are released by these eight turns of the citric acid cycle?

16

A boy is red-green colorblind, but his mother, father, and all of his grandparents have normal color vision. Knowing that red-green colorblindness is controlled by a gene on the X chromosome, and assuming that the boy's colorblindness was not due to new m

XBXb, XBY

To start transcription in eukaryotic cells, RNA polymerase needs

transcription factors to help it bind to a promoter

In which of the following actions does RNA polymerase differ from DNA polymerase?

RNA polymerase can initiate RNA synthesis, but DNA polymerase requires a primer to initiate DNA synthesis

A cell in the lining of the stomach is structurally and functionally different from a brain cell mainly because it

differs in what genes are expressed

If a substance is said to have a high specific heat, that means that it

heats and cools more slowly than most substances

Which of the following must exist in a population before natural selection can act upon that population?

genetic variation among individuals

In snapdragons, heterozygotes have pink flowers, whereas homozygotes have either red or white flowers. When a pink-flowered snapdragon is crossed with a pink-flowered snapdragon, what proportion of the offspring would be predicted to have white flowers?

25%

Which is most likely to happen to a human autosomal aneuploid?

spontaneous abortion

In humans, wet earwax is a dominant trait governed by normal Mendelian inheritance for a single autosomal gene with two possible alleles; the other trait, dry earwax, is recessive. A woman with wet earwax has one child, and that child has dry earwax. What

heterzygous

In pea plants purple flower color is dominant over white flower color. A pea plant that is homozygous purple-flowered is crossed with another pea plant that is heterozygous. Which answer fits the predicted genotype(s) of their offspring with respect to fl

1 AA : 1 Aa

A phylum is divided into ____ as the next taxonomic level.

classes

The various species of Galapagos finches are closely related to each other genetically; their next closest genetic relatives are found

on the nearby mainland of South America

When columbines with lavender flowers are mated they produce offspring that make either dark purple, lavender, or white flowers. The ratio is 1 dark purple: 2 lavender: 1 white. Based on this, inheritance of flower color in columbines is apparently an exa

incomplete dominance

You are genetic counselor, and a couple comes to you with concerns that if they have a child together it could have hemophilia. The man does not have hemophilia. The woman does not have X-linked hemophilia either, but her father does have it. Which of the

each of their male offspring will have a 50% chance of having hemophilia, and while their female offspring should not have hemophilia they will each have a 50% chance of being carriers

Which of the following is the most appropriate term to use for a structure that has lost most or all of its ancestral function in a given species but that is still present in some form in that species? An example of such a structure would be the appendix

vestigial

In his transformation experiments, Griffith observed that

mixing a heat-killed pathogenic strain of bacteria with a living nonpathogenic strain can convert some of the living cells into the pathogenic form

In peas, the allele for tall (T) is dominant over short (t), and the unlinked gene for seed color has the allele for yellow seeds (G) dominant over green seeds (g). What is the predicted phenotypic ratio for offspring from this cross: ttgg x TtGg

1 tall, yellow: 1 tall, green: 1 short, yellow: 1 short, green

The place where RNA polymerase first associates with DNA so that transcription can begin is called the _ and is located _ of the transcribed region

promoter; upstream

Translation ends when a stop codon is at the site, allowing a/an ____ to enter there and then cause the translation machinery to fall apart and release the new polypeptide.

A; termination factor

A woman is red-green colorblind, and she mates with a man who has normal color vision. Knowing that red-green colorblindness is controlled by a gene on the X chromosome, you can predict that if they produce children the odds are that

all of the boys and none of the girls will be colorblind

Which of the following nucleotide sequences represents the complementary sequence that would bind to the DNA strand5' - TCATGG - 3'?

3' - AGTACC - 5'

Charles Darwin first published On the Origin of Species by Means of Natural Selection in

1859

One gene determines red vs. white flowers in pea plants, and another determines axial vs. terminal flowers. Two true-breeding stocks of pea plants are crossed. One parent has red, axial flowers and the other has white, terminal flowers; all F1 individuals

9/16

The DNA of an organism is studied and found to contain 34% cytosine. This organism should have % thymine and % guanine in its DNA

16; 34

In Drosophila melanogaster the allele for long wings is dominant over the allele for vestigial wings and the allele for a gray body is dominant over the allele for a black body. A testcross was done to check for genetic linkage between the genes for these

10 map units

The process of transcription refers to the direct use of information encoded in _ to make _

DNA; an RNA strand

You are genetic counselor, and a couple comes to you with concerns that if they have another child together it could have cystic fibrosis. The man does not have cystic fibrosis, but his brother did. Genetic tests reveal that both the man and the woman are

any child that they produce will have a 25% chance of having cystic fibrosis

Stopping transcription in eukaryotes requires

generation of a poly-A tail

A boy is red-green colorblind, but his biological parents and grandparents all have normal color vision Assuming that the boy's colorblindness was not due to new mutations, what are the genotypes for his maternal grandparents? Use XB for the dominant (nor

XBXb, XBY

Natural selection is based on all of the following except

individuals adapt to their environments and, thereby, evolve

Muscle cells and nerve cells in one species of animal owe their differences in structure to

differences in gene expression

Substitution of one base pair for another in a coding region of a gene can result in a __ mutation that changes a codon that once coded for an amino acid to code for a different amino acid

missense

In humans, phenylketonuria (PKU) is a/an ______ genetic disorder

autosomal recessive

What is the predicted phenotype ratio for human children if their mother's genotype is IAIA for blood type and their father is IAIB?

1/2 A: 1/2 AB

Histone H1 interacts with linker DNA to form the _________ .

packed nucleosomes (30 nm fiber)

Individuals who are genetic carriers for sickle cell anemia do not actually have sickle cell anemia but do have a heterozygote advantage in some parts of the world because they are more resistant to ____

malaria

The process of adding the correct amino acid onto a tRNA molecule is catalyzed by

an aminoacyl-tRNA synthetase

In aerobic respiration, energy released by the electron transport chain is used to pump H+ ions into which location?

mitochondrial intermembrane space

Which of the following is the most accepted hypothesis as to why invasive species take over communities into which they have been introduced?

Invasive species are not held in check by the predators and agents of disease that have always been in place for the natives

Although different species of dragonflies will often attempt to mate, the differences in genitalia between the species makes the mating impossible. This is an example of what type of reproductive isolating mechanism?

mechanical isolation

A small group migrates and colonizes a new area. This area is geographically isolated from the original population, and the colony population remains genetically separated from the original population for millions of years. Then, when the populations come

allopatric speciation

Which of the following disrupts genetic equilibrium (Hardy-Weinberg equilibrium) by allowing genetic drift to play a large role in changing the population?

small population size

This aquatic biome is the interface between land and the sea, and is periodically submerged and exposed on a daily basis, twice daily in most places.

intertidal zone

Tay-Sachs disease is inherited as an autosomal recessive genetic disorder in humans that causes progressive deterioration of nerve cells and of mental and physical abilities. Prior to modern genetic testing, the rate of Tay-Sachs among births to Ashkenazi

0.037

A diploid cell that is 2N = 6 undergoes all of meiosis, including all cell divisions. The result is

4 cells, with 3 chromosomes each

The mass extinction event that cleared the way for the rise of the dinosaurs to prominence occured at the end of the _ period.

Triassic

Oxygenation of the Earth's atmosphere was required to allow life to exist on the Earth's surface because it set up conditions to:

block much of the UV radiation from the sun

Which of the following is an almost certain consequence of the loss of species biodiversity associated with the sixth extinction?

Some medical treatments will not be available, causing many humans to live shorter lives.

Which of the following would BOTH a prokaryotic cell and a eukaryotic cell have?

ribosomes

In triacylglycerols, fatty acid chains are linked to glycerol via

ester linkages

Which model would account for the abrupt appearance of a new species in the fossil record, with little or no evidence of intermediate forms?

punctuated equilibrium

Which of the following is the primary cause of seasons on Earth?

the tilt of Earth's axis

Which of the following is caused by excessive nutrient runoff into lakes?

eutrophication

In the breakdown of glucose via aerobic respiration, which of the following stages directly (by itself) produces the LEAST amount of ATP?

formation of acetyl-CoA (pyruvate oxidation)

Which of the following interspecific interactions is a - / - interaction?

competition

The Chicxulub crater, an iridium anomaly, tektites in Haiti, and deposits in the Brazos River bed in Texas from a giant tsunami (that also hit the land area that is now Auburn, Alabama) are all dated to

about 65 million years ago

Fossils from the __ period include the earliest amphibians and insects, and indicate that during this period in the seas the jawed fishes diversified and dominated while on land the vascular plants diversified and dominated.

Devonian

A pond is seined to measure the population of red spotted newts (Notophthalmus viridescens viridescens) in the bond. In the first seining 507 newts are captured, marked by clipping off the second left front toe, and released back into the pond. Two days l

2700

This kind of substance can both catalyze a variety of reactions and store genetic information, supporting the view that the early "world" of life centered on molecules of this type.

RNA

Which of the following is an example of Batesian mimicry?

a non-venomous snake that looks like a venomous snake

As N approaches K for a certain population, which of the following is predicted by the logistic population growth equation?

the growth rate will approach zero

The nearly worldwide presence of banded iron formations that date to about 2.5 billion years ago indicates that at that time

some process released large amounts of O2 into the oceans

A methyl group is best described as

nonpolar and hydrophobic

Some global warming models predict that, if permafrost in the tundra regions in the northern hemisphere melts, atmospheric CO2 levels will increase. Which of the following statements best explains this prediction?

All of the undecayed organic material would be subject to decomposition following a thaw, which would lead to incredible increase in global cellular respiration, and add to atmospheric CO2

The statement "parents normally have two alleles for each gene; these alleles are assigned to different gametes" is a modern version of Mendel's law of _ , while that statement "segregation of any one pair of alleles is independent of the segregation of o

segregation; independent assortment

The Cenozoic era has been marked by massive diversification of and some measure of dominance of the planet by

- mammals
- insects
- birds
- flowering plants

Which of the following are considered to be likely requirements for the production of life on the early Earth?

- water with dissolved mineral irons
- abundant energy sources
- little or no free oxygen
- plenty of time for rare events to occur

A diploid cell that is 2N = 6 undergoes mitosis and cytokinesis. The result is

2 cells, with 6 chromosomes each

This terrestrial biome has cool, wet winters and long, warm, dry summers. Fires are common in this biome, with the plants mostly being shrubs and small trees that are fire-adapted

chaparral

In a polysaccharide such as cellulose, sugar monomers are joined together by

glycosidic linkages

Fossils in the Burgess shale record the "Cambrian explosion," a tremendous expansion in diversity of multicellular organisms that occurred

about 500 million years ago

You are most likely to observe primary succession in a terrestrial community when you visit a(n)

recently created volcanic island

In humans there is a gene for dry or wet earwax, with the allele for wet earwax (A) dominant over the allele for dry earwax (a). In an isolated population of humans the frequency of the individuals with dry earwax is 0.64, or 64%. If the population is in

0.04

Which of the following characterizes relatively K-selected populations?

offspring with good chances of survival

Cell membrane proteins called pumps use energy (typically from ATP) to move substances across cell membranes against their concentration gradient. An example would be moving Ca++ ions into a cell when the cell already has a higher concentration of Ca++ io

active transport

Which of the following best describes resource partitioning?

slight variations in niche allow similar species to coexist

The enzyme RUBISCO is involved in catalyzing which process?

addition of CO2 to RuBP

Wind, temperature, sunlight, and precipitation are the main components of

climate

Oxygen tends to form 2 covalent bonds, while carbon tends to form 4 covalent bonds. This is mostly because oxygen has _ valence electrons and carbon has _ valence electrons.

6; 4

This aquatic biome is an area with water-saturated soil with at least periodic standing water

wetland

The most widely accepted date for the age of the Earth based on scientific evidence is about

4.6 billion years

Disruptive selection, where there is selection against hybrids, can genetically split a population in the same geographic location into two or more species. This process of speciation is called

sympatric speciation

How does carbon normally enter into organic molecules, and thus into ecosystems?

photosynthesis

Although a horse and a donkey can mate and produce a mule that survives to adulthood, the mule will not be able to have offspring. This is an example of what type of reproductive isolating mechanism?

hybrid sterility

The main structural components of plant cell walls are _ molecules

cellulose

To measure the population density of Florida black bears (Ursus americanus floridanus) in the Okefenokee Swamp, 87 bears are captured, each marked with a small permanent tattoo inside the left ear, and then released. A few months later another surveying h

599

How many electrons does a carbon atom have in its outer shell?

4

Cellulose is the main component of which cellular structure in plants?

cell walls

Which of the following is found in a eukaryotic cell but not a prokaryotic cell?

mitochondria

Which of the following function groups is an acid?

carboxyl group

A molecule has a carbon atom with the following bound to it: an H, a COOH (or COO-), an NH2 (or NH3+), and a CH3. What kind of molecule is it?

amino acid

Which of the following is NOT true about enzymes?

enzymes are consumed by the reaction they catalyze

The purpose of aerobic respiration for an organism is to

get chemical energy from molecules like glucose

O2 in the biosphere comes mainly from

non-cyclic electron transport

A cell is diploid, with 2n = 12. If it goes through both mitosis and cytokinesis, the result is

2 cells; 2n = 12

A cell is diploid, with 2n = 12. If it goes through meiosis with cytokinesis in each telophase, the result is

4 cells; n = 6

An animal zygote cell typically divides via

mitosis

A human gamete has ____ autosomes

22

A human gamete has ____ chromosome pairs

0

An anticodon is physically found in cells as

3 nucleotides in a row in tRNA

The removal of introns and joining of exons in mRNA is

splicing

A new, inherited mutation will always

increase genetic polymorphism

What is true about genetic drift and gene flow?

- genetic drift tends to increase genetic variation between populations
- gene flow tends to decrease genetic variation between populations

In trout lilies the allele for red pollen, R, is dominant over the allele for yellow pollen, r. In a survey of a population of trout lilies you find that the frequency of individuals producing yellow pollen is 0.49, or 49%. If the population is in genetic

0.42

In humans there is a gene for dry or wet earwax, with the allele for wet earwax (A) dominant over the allele for dry earwax (a). In an isolated population of humans the frequency of the individuals with wet earwax is 0.99, or 99%. If the population is in

0.81

Phenylketonuria is inherited as an autosomal recessive genetic disorder in humans. The rate of phenylketonuria among human births in the United States is about 1 in 12,000. If the U.S. population is in genetic equilibrium (Hardy-Weinberg equilibrium) for

0.018

Hybrid inviability and hybrid breakdown are reproductive isolating mechanisms that are

postzygotic barriers

Although tigers and lions will mate in zoos to produce tigons and ligers, even where their range overlaps in nature they do not mate because they mate in different locations. This is an example of what type of reproductive isolating mechanism?

habitat isolation

Although bullfrogs and leopard frogs will occasionally mate in the wild, their embryos do not develop into living tadpoles. This is an example of what type of reproductive isolating mechanism?

hybrid inviability

Incompatibility in the physical structure of genitalia in different fruit fly species that prevents successful cross-species mating is an example of what type of reproductive isolating mechanism?

mechanical isolation

Oxygenation of the Earth's atmosphere was required to allow life to exist on the Earth's surface because it set up conditions to

block much of the UV radiation from the sun

Which model for where and how life on Earth began relies on deep-sea hydrothermal vents, similar to some environments found on Earth today?

iron-sulfur world hypothesis

The mass extinction event that cleared the way for the rise of the dinosaurs to prominence occured at the end of the _ period

Triassic

This kind of substance can both catalyze a variety of reactions and store genetic information, supporting the view that the early "world" of life centered on molecules of this type

RNA

Fossils from the __ period have abundant numbers and diversity of trilobites, brachiopods, and molluscs as well as the first coral reefs and the first terrestrial plants

Ordovician

Many orchids in tropical forests grow on branches in the tree canopy. These orchids do not harm or help the trees that they grow on in any measurable way. Which of the following terms would best describe this interaction?

commensalism

How does phosphorus normally enter ecosystems?

rock weathering

This terrestrial biome usually has long, cold winters and has widely varying amounts of annual precipitation, with periodic droughts common. It is dominated by cone-bearing trees

taiga

A pond is seined to measure the population of red spotted newts in the bond. In the first seining 287 newts are captured, marked by clipping off the second left front toe, and released back into the pond. Two days later the pond is seined again, and this

2394

To measure the population of monarch butterflies occupying a particular park, 100 butterflies are captured, marked with a small dot on a wing, and then released. The next day, 200 butterflies are captured, including the recapture of 20 marked butterflies.

1000

How many atoms are in the valence shell of an atom of carbon?

4

A neutral atom of Manganese has an atomic number of 25. This means that the atom has

25 neutrons, 25 protons, and 1 valence shell electron

3 molecules are put in the same extremely high temperatures. One molecule is held together by ionic bonds, one molecule by covalent bonds, and one with only hydrogen bonds. In which order will the molecules melt (their bonds breaking apart)?

hydrogen bond, ionic bond, covalent bond

Which of the following properties of water allow it to go up the root systems of trees?

- cohesion
- adhesion

Which of these statements is NOT true about buffers?

Raises the pH of a solution

If a solution goes from a pH of 6 to a pH of 3, then it is _______ times more _________

1000; acidic

Which of the following is NOT matched correctly?

methyl group linkage -lipids

Mitochondria and chloroplasts are found in all cells

false

In which of the following protein structure levels are beta pleats found?

secondary

Which of the following macromolecules contribute to maintaining membrane fluidity?

steroids (lipids)

In the kidney, water has to move extremely rapidly in and out of the organ in order to respond to the changing internal environment. Therefore, the cells in the kidney must have many ______________ in their cell membranes

aquaporins

When osmosis is occurring across a semipermeable membrane, water will always move toward the ___________ solution that contains a ______________ amount of solute.

hypertonic; greater

A cell is dropped into a solution and it quickly expands in size until it bursts. What type of solution was the cell probably dropped into?

hypotonic solution

A 0.9% NaCl solution is isotonic to red blood cells. If red blood cells are placed into a 9% NaCl solution, what will happen to them?

the cells will shrink

Strychnine is a colorless highly toxic alkaloid that causes muscular convulsions and eventual death through asphyxia. Strychnine binds to glycine receptors preventing glycine (an inhibitory neurotransmitter) from binding. Strychnine is an example of

a competitive inhibitor

Which of the following steps does not require oxygen?

- glycolysis
- fermentation

Which of the following steps occur in the mitochondrial matrix?

krebs cycle

What is the final electron acceptor in oxidative phosphorylation?

O2

What is the net ATP for glycolysis?

2

What is the net ATP for the Krebs Cycle?

0

What is the main function of the Krebs cycle?

to produce NADH and FADH

What is the final electron acceptor in photosynthesis?

NADP+

What is the electron donor in photosynthesis?

H2O

Which of the following statements accurately describes CAM plants?

they complete carbon fixation and the Calvin cycle at different times of the day

How many turns of the Calvin cycle create ONE molecule of glucose?

6

Where does the light-dependent phase of photosynthesis occur?

the thylakoid membrane

What is the name of the enzyme that catalyzes the fixation of carbon to the RuBP molecule in the first step of the Calvin cycle?

rubisco

In which phase of interphase does DNA get replicated?

S

In which stage of mitosis do the chromosomes line up at the epiphyseal plate?

metaphase

In which stage of meiosis does "crossing over" occur?

prophase I

In which stage of meiosis do homologous chromosomes separate?

anaphase I

In humans, somatic cells have _____ chromosomes and gametic cells have _____

46; 23

Mitosis produces _____ ________ daughter cells

2 diploid

Meiosis produces _____ ________ daughter cells

4 haploid

Which of the following statements occur in meiosis?

- law of independent assortment
- law of segregation
- recombination of alleles on the chromosome
- crossing over

During DNA replication, a segment of chromosomal DNA was removed from chromosome 1 and later found on chromosome 12. What is this an example of?

translocation

A mutation in the DNA resulted in a single nucleotide polymorphism. That is, a single nucleotide was deleted on the coding strand of DNA. What is a negative outcome from this mutation?

- frameshift mutation
- the amino acid sequence of the corresponding protein will be changed
- the tertiary and quaternary structures of the protein will be changed

During mRNA processing, a poly-A tail and a 5' cap is added. Additionally, all of the exons are removed as they are non-coding regions

false

Which of the following statements are possible after a cell becomes unfit to pass a replication checkpoint?

- apoptosis
- the cell enters G0 and stops dividing
- the cell ignores the checkpoint, continues to divide, and becomes cancerous

In which direction does DNA polymerase run?

5' to 3'

Which of these statements is correct about the leading strand of DNA replication?

replication is continuous and does not stop

Which of these forms of RNA form the main structural and catalytic elements of ribosomes?

rRNA

Which of the following is NOT a characteristic of a population in Hardy-Weinberg equilibrium?

a large population size

Which of the following is considered to be a postzygotic reproductive barrier?

reduced hybrid fertility

In a valley with a river, a population of snake lived and reproduced as the same biological species. Over time, the river grew and grew until it filled the valley and some snakes were pushed to each side of the valley and the two halves could not reach ea

allopatric speciation

In the Hardy-Weinberg equation, what does ??2stand for?

the frequency of the dominant allele

The bottleneck effect and the founder effect are both examples of

genetic drift

In mallard duck populations, the female mallards have brown feathers and the male mallards have different, more colorful feathers. Female mallards prefer males with the most brightly colored feathers. This is an example of

- sexual dimorphism
- intersexual competition

Both birds and bats have wings that allow them to fly, but the way that their wings are structured are different. What is this an example of?

analogous structures

Both whales and snakes have pelvic bones, but neither of them have hind legs. What is this an example of?

vestigial structures

Which of the following are in the correct order from smallest to largest?

organism, population, community, biome, biosphere

An autosomal recessive disease results in malformed hemoglobin proteins which, in turn, causes all blood cells to become malformed as well. Individuals who inherit the trait also inherit the disease. However, carriers of this trait are immune to malaria.

sickle cell anemia

What is a reproductive isolating mechanism? What are the two ways reproductive isolating mechanisms can be classified?

- prezygotic: prevent fertilization (zygote formation) between gametes of two species
- postzygotic: reproductive isolation after fertilization has occurred

Habitat isolation

isolation by differences in habitat occupied at the time of mating
- prezygotic

Temporal isolation

isolation by differences in timing of mating
- prezygotic

Behavioral isolation

differences in behavior that cause reproductive isolation
- prezygotic

Mechanical isolation

similar species have structural differences in reproductive organs
- prezygotic

Gametic isolation

mating occurs, but the sperm and egg cannot fuse
- prezygotic

Hybrid inviability

zygote formed from the mating of two species does not develop normally or the embryo is aborted, or if development is completed the offspring is very frail
- postzygotic

Hybrid sterility

a zygote of a hybrid proceeds through normal development, but is reproductively sterile
- postzygotic

Hybrid breakdown

a zygote of a hybrid proceeds through normal development, and the interspecific hybrid reproduces, but the F2 generation and beyond may have trouble reproducing
- postzygotic

Explain the difference between anagenic and cladogenic speciation.

- anagenic: gradual change of one species into a new form where the new form replaces the old form
- cladogenic: two or more species are present where only one existed before, these species share a common ancestor

Explain the difference between allopatric and sympatric speciation. Are these Anagenic or Cladogenic?

- allopatric: one population becomes geographically separated from the rest of the species
- sympatric speciation: a species achieves reproductive isolation and evolves in the same geographic location as its ancestral species
-both examples of cladogenic

Are polyploidy and autopolyploidy examples of allopatric or sympatric speciation?

yes, closely related species produce a hybrid that must double its chromosome number to reproduce successfully; a new, viable hybrid species is thus formed

Describe disruptive selection?

individuals with extreme phenotypes experience the highest fitness, and those with intermediate phenotypes have the lowest.

Is adaptive radiation an example of allopatric or sympatric speciation?

adaptive radiation (rapid production of many species from a common ancestor) is most easily produced by a combination of allopatric speciation and sympatric speciation. pioneers on an island, or pioneering fish such as cichlids in Lake Victoria, are separ

What would be the mRNA transcript that would be made complimentary to the DNA sequence:
3'-CGAGCTACGGTCTCAAAATTCGACCT-5'

5'-GCUCGAUGCCAGAGUUUUAAGCUGGA-3'

During DNA replication, the ____________ strand is assembled in the ________ direction that the DNA double helix unwinds and is produced by __________ replication

leading; same; continuous

The place where RNA polymerase first associates with DNA so that transcription can begin is called the _________ and is located ________ of the transcribed region

promoter; upstream

The process of adding the correct amino acid onto a tRNA molecule is catalyzed by _______

an aminoacyl-tRNA synthetase

What is the difference between microevolution and macroevolution?

macroevolution is the formation of species, while microevolution is the change of a population over time

The process of transcription refers to the use of information encoded in _______ to make __________

DNA; an RNA strand

The DNA of an organism is studied and found to contain 20% adenine. This organism should have ____ % thymine a ____% cytosine in its DNA

20; 30

Silent mutation

does not change what the amino acid is coded for

Nonsense mutation

results in the formation of a stop codon and premature termination of the protein sequence

Frameshift mutation

mutation that shifts the "reading" frame of the genetic message by inserting or deleting a nucleotide

Missense mutation

causes a change in what an amino acid is coded for

Pea flowers may be purple (P) or white (p). Pea seeds may be round (R) or wrinkled (r). What proportion of the offspring from the cross PpRr�PpRr will have purple flowers and wrinkled seeds?

3/16

In humans, the gene for cystic fibrosis is linked to a gene for a rare form of "blue/yellow" colorblindness.Both of these are recessive. In a study of a small population, several matings were recorded between individuals heterozygous for both genes and in

10 map units

Peptide bonds are typical bonds between?

amino acids

Which of the following describes RNA?

- single-stranded
- contains uracil
- has the sugar ribose
- has three main forms

In the Hershey and Chase Experiment, the pellet was radioactive after the bacteria had been infected with 32P-labeled viruses and centrifuged why?

Bacteria were centrifuged to form the pellet, and they had incorporated radioactive DNA

Which of the following is a stop codon?

UAG, UGA, UAA

At the EPA site, where does the new amino acid chain enter?

A site

Which direction does DNA synthesize?

5' to 3'

What is true of DNA?

- made of deoxyribose sugar
- has the base thymine
- nucleotides are linked by 3', 5' phosphodiester linkage
- double helix structure

Which of the following is homozygous recessive?

rr

Translation ends when a stop codon is the __ site, allowing a/an __ to enter there and cause the translation machinery to fall apart and release the new polypeptide

A; termination factor

What are Mendel's four ideas of gene inheritance?

- law of segregation
- law of independent assortment
- dominant traits prevail in phenotype
- each trait has two alleles

Define the Law of Segregation

during gamete formation, the two alleles at a gene locus segregate from each other

Define the Law of Independent Assortment

the alleles of two (or more) different genes get sorted into gametes independently of one another

Linkage group

all genes on a chromosome tend to be inherited together

How does genetic mapping predict recombination of genes? What is a map unit?

the closer genes are to each other on a chromosome, the more likely they are to be inherited together. The farther they are on a chromosome, the less likely they are to be inherited together.
map units = 1% recombination

What is the difference between incomplete dominance and codominance?

- incomplete dominance results in a mix of both the dominant and recessive phenotype
- in codominance both dominant traits appear in the phenotype

Epistasis

a form on non-Mendelian inheritance in which one gene is capable of interfering with expression of another
- ex. albinism

In humans, one form of polydactyly (extra fingers and toes) is controlled by a single autosomal gene with two possible alleles; the dominant allele leads to polydactyly, the recessive is for the normal number of fingers and toes. A woman with this form of

50% Ff

In roses assume that red or yellow flower color is controlled by a single gene with two alleles. Crossing roses with yellow flowers with each other yields only offspring that produce yellow flowers, but when you cross roses with red flowers with each othe

1/2 red (heterozygous)
1/2 yellow

Pea flowers may be purple (P) or white (p). Pea seeds may be round (R) or wrinkled (r). What proportion of the offspring from the cross PpRr�PpRr will have white flowers and wrinkled seeds?

1/16

If a heterozygous plant is allowed to self-pollinate, what proportion of the offspring will also be heterozygous?

1/2

Human blood groups are governed by three alleles: IA,IB, and i. IA and IB are codominant and i is recessive to both. A man who has type B blood and a woman who has type A blood could have children of which of the following phenotypes?

A, B, AB, O

Natural selection

selection of advantageous traits of individuals that change the genetic makeup of populations over successive generations

Evolution can be seen over the course of one generation

false

Evolution can happen to a specific individual

false

Evolution

the natural selection of traits that produce individuals more suited to their environment through time

Adaptation

a characteristic that improves an individual's ability to survive and reproduce in a particular environment.

What four general observations were the basis of Darwin's theory of evolution?

- overproduction: each species produces more offspring than will survive to maturity
- variation: individuals in a population vary, and some of the variation is heritable
- competition: there is competition among the individuals of a population for limite

Describe the difference between a homologous structure and an analogous structure

- analogous structures: have superficial similarity in function (bird wing and insect wing)
- homologous structures: have similar form due to common evolutionary origins (dolphin flipper and human hand)

Convergent evolution

the independent evolution of similar features in different lineages (wings in birds and bats)

Vestigial structures

a feature of an organism that once had a role in the evolutionary history of a species but now no longer functions

Biogeogrpahy

the study of past and present distribution of organisms
- ex. organisms on islands are more closely related (in form and genetically) to those from the nearest mainland and not those from similar island

The outcome of natural selection is random

false

Artificial selection

the idea that traits can be selectively bred by humans to produce different varieties

What are the DNA bases and their pairs?

- purines: adenine (A) and guanine (G)
- pyrimidines: thymine (T) and cytosine (C)
A-T
C-G

Nucleotides are linked by

hydrogen bonds

Conservative replication

both parental strands remain together after replication, and the two newly synthesized strands would form a second double helix

Semiconservative replication

each new DNA molecule consists of one new strand and one old strand

Dispersive replication

old and new DNA are interspersed in both stands following replication

What is required for DNA replication?

the coordinated activity of many enzymes and other proteins and the presences of nucleotide triphosphates

DNA helicase

unwinds and opens DNA during replication

Single-strand DNA-binding proteins

attach to the separated DNA strands to prevent them from closing during replication

Topoisomerases

break and rejoin DNA strands, resolving knots and strains that occur

DNA polymerase

directs synthesis of new DNA strands by joining individual nucleotides
- moves in a 5'-3' direction, adds nucleotides onto the 3' end

Primase

starts the strand by making an RNA primer that is a few ribonucleotides long

Leading strand

strand being synthesized, has its 3' end at the fork, synthesis proceeds continuously in the direction that the fork moves

Lagging strand

has its 5' end at the fork; it must be synthesized in the opposite direction from the leading strand

Okazaki fragments

small fragments of DNA produced on the lagging strand during DNA replication, joined later by DNA ligase to form a complete strand.

DNA ligase

connects the Okazaki fragments to connect the DNA

Nucleosomes

the main packaging mechanism for eukaryotic DNA. made up of 8 protein subunits acting like a spool for the DNA thread

Histones

protein molecules around which DNA is tightly coiled in chromatin. are positively charged and are thus able to associate with the negatively charged phosphates of the DNA backbone

Gene

information for making specific proteins

RNA

intermediary between the information encoded in DNA and the production of proteins

What are the three main forms of RNA and what do they do?

- mRNA (messenger RNA): copies the actual instructions from the gene
-tRNA (transfer RNA): links with amino acids and bring them to the appropriate sites for incorporation in proteins
-rRNA (ribosomal RNA): main structural and catalytic components of ribo

List the steps of Transcription and what happens in each step

- initiation: requires a promoter, RNA polymerase opens and unwinds DNA, RNA polymerase begins building an RNA strand in 5'?3' direction complementary to the template strand, 1 RNA strand is produced
- elongation: transcription continues in a linear fashi

What is the genetic code?

the information actually used for making proteins

What is a codon? How are they read/written?

- sequences of three bases that instruct for the addition of a particular amino acid
- codons are read in sequences of 3 bases on mRNA
- always written in 5?3 direction

Describe Translation and all its steps

- initiation: initiation complex is formed, initiation factors helps bind the initiator tRNA to mRNA, recognizes the codon AUG and codes for Met
- elongation: elongation factors assist in getting charged tRNA to bind to ribosome
- termination: a stop codo

What is the difference between Eukaryotes and Prokaryotes for translation/transcription?

transcription:
- eukaryotes: use DNA pol II and III
- prokaryotes: use DNA pol I
translation:
- eukaryotes: require ATP
- prokaryotes: require GTP

What are the interrupting coding sequences called?

introns and exons

What is the process of removing introns called?

splicing

How does alternative RNA splicing work?

one DNA sequence directs synthesis of two or more different polypeptides

What are mutations?

changes in an organism's DNA sequence

In which phase of aerobic respiration is oxygen required?

oxidative phosphorylation

Which of the following is a way organisms control fluidity?

changing the fatty acid profile of their membranes

How many molecules of NADH would be produced by five turns of the Krebs cycle?

15

Which of the following processes typically occur during anaphase?

kinetochore microtubules shorten behind the moving chromosomes

Diploid cells give rise to haploid cells during

meiosis

Which of the following lists eukaryotic cell cycle phases in a correct chromosomes?

telophase, interphase, prophase, metaphase, anaphase

In the phospholipid bilayer, the heads (which are on the outside) are?

hydrophilic

What is the net ATP per glucose in fermentation?

2

Homologous chromosomes separate during

meiosis I

Which type of electromagnetic radiation has the highest amount of energy?

gamma radiation

Crossing over for genetic recombination occurs in what phase of meiosis?

prophase II

In eukaryotes, what is the final electron acceptor?

O2

In anaphase II of meiosis you should find that sister chromatids

have broken apart at the centromere

An unspecified animal with a diploid number 2n= 16 chromosomes will have _____ chromosomes in its somatic (body) cells and_____ chromosomes in its gametes

16; 8

A small molecule can travel directly from the cytoplasm of one plant cell to the cytoplasm of an adjacent plant cell through

desmosomes

Where can a substrate bind to an enzyme?

active site

Suppose that a cell has 30 chromatids at prophase of mitosis. After mitosis and cytokinesis end, the two resulting daughter cells should have how many chromosomes each?

15

When a sample is centrifuged, the material that is packed at the bottom of the test tube is the _____

pellet

Which of the following does NOT happen in prophase of mitosis in animal cells?

homologous chromosomes pair up

Where does substrate bind to an enzyme?

active site

What term describes where a noncompetitive inhibitor would bind to an enzyme?

allosteric site

What isn't a part of the electron transport chain?

ATP synthase

Acetyl-CoA enter the citric acid cycle by

reacting with oxaloacetate, forming citrate and freeing CoA

In eukaryotes, the replication of chromosomal DNA occurs in:

S phase

What is the electron acceptor in noncyclic electron transport in photosynthesis?

NADP+

The process that allows proteins (H+) to move against their concentration gradient across a biological membrane using a protein channel would be best termed as

active transport

Suppose that a cell has 24 chromatids at prophase of mitosis. After mitosis and cytokinesis end, the resulting daughter cells should have how many chromosomes each?

12

Carbon Dioxide (CO2) is released during which of the following stage(s) of aerobic respiration?

both the oxidation of pyruvate to acetyl CoA and the citric acid cycle

Which of the following types of cell-cell contacts are adjacent to each other and held together by a tight seal?

tight junctions

Which of the following are properties of water due to hydrogen bonding?

- ice floats in water
- nonionic polar substances tend to dissolve in water
- water moderates temperature more than most substances
- water exhibits highly cohesive behavior

Sparrows are birds and have wings. Falcons are birds and have wings. All birds have wings. The third statement being concluded based off of the first two statements is an example of ____.

inductive reasoning

Phyla are divided into the next taxonomic order

classes

Organisms that manufacture their own food from simple materials are ___.

autotrophs

How many covalent bonds will a neutral Carbon atom tend to form?

4

If a neutral atoms has 12 protons and 17 neutrons, how many electrons will it have?

12

Water is which of the following?

a compound and a molecule

Which of the following is the strongest type of bond?

covalent

What is being oxidized when NaCl is formed?

Na

An organism is a multicellular eukaryote with cell walls whose cell walls are made of chitin. It could belong to which of the following kingdoms?

fungi

In the name, Aubuis tigris, what is the specific epithet

tigris

What kind of bondage results in partial charges occurring due to unequal sharing of electrons?

polar covalent bond

Water is an excellent solvent for other ____ substances

polar

Acids are proton ____, and bases are proton _____

donors, acceptors

Which of these would act as a pH buffer?

- weak acid
- weak base

An organic compound with a tetrahedron will have bond angles that are how many degrees apart?

109.5

A longer polymer is formed by removing a water molecule through ___

dehydration synthesis

Which major class are enzymes found in?

proteins

A molecule with the chemical formula C12H24O5 is probably a

lipid

Which of these functional groups is hydrophobic?

methyl group

An ester linkage is formed between

a fatty acid and glycerol

Which of these is NOT a component of an amino acid?

glycosidic linkage

Cystine is essentially _______ and forms ______ with other cysteine molecules

nonpolar; disulfide bridges

The _______ of a protein is held together by ______

- secondary structure: hydrogen bonds
- quaternary structure: two or more polypeptide chains
- tertiary structure: R groups
- primary structure: amino acids

DNA double helix has

hydrogen bonds and antiparallel components

How old is the Earth and what evidence supports it?

4.6 billion years old
supported by radioisotope dating of:
1. oldest known Earth minerals (date to 4.4 billion years ago)
2. oldest known rocks on Earth (4.1 bya)
3. oldest known meteorites (4.6 bya)

What did the early atmosphere of the Earth consist of?

CO2, H2O, CO, H2, N2, and small amounts of NH3, H2S, and CH4. Note the lack of O2 which is a major component of today's atmosphere

What are four requirements for the current chemical evolution model that were likely met in the early Earth?

1. little or no free oxygen
2. abundant energy sources (Earth had no atmosphere to block out the UV rays of the sun.)
3. chemical building blocks of water, dissolved mineral ions, and atmospheric gases
4. time

Operin and Haldene

independently proposed that organic molecules could form spontaneously from simpler raw materials when sufficient energy is supplied in a reducing (electron-adding) environment

Miller and Urey

made a "reducing atmosphere" of H20, H2, NH3, and CH4 in a spark chamber. They found afterwards that amino acids and other organic compounds had been formed. this experiment was made to mimic what was thought at the time to have been Earth's early atmosph

prebiotic broth hypothesis

life began from an "organic soup" in oceans

bubble hypothesis

a variation on the prebiotic broth, with only "oily bubbles" from an organic soup interacting with land surfaces at shallow seas or seashores

iron-sulfur hypothesis

life began from an "organic soup" interacting with mineral surfaces at hydrothermal vents in the ocean floor, with abundant iron and sulfur there impacting the early metabolism that developed

deep-hot biosphere hypothesis

life began in an "organic soup" deep within the Earth

exogenesis

earth was seeded with life from an extraterrestrial source

protobionts

collections of abiotically produced molecules surrounded by a membrane-like structure

microspheres

type of protobiont formed by adding water to abiotically formed polypeptides. microspheres can grow, divide, and maintain internal chemistry different from their surroundings

RNA World Hypothesis

RNA can catalyze a variety of reactions, including some self-catalytic reactions and can also store genetic information.

in vitro evolution

shows that the RNA world hypothesis is feasible- selection can act on self-replicating RNA molecules in vitro

microfossils

first fossil evidence for life found in continental shields rocks

stromatolites

rocklike structures made up of layers of bacteria and sentiment. in some areas, stromatolites are still being formed today.

What were most likely the first bacteria to be photosynthetic organisms?

cyanobacteria were most likely to use H2O as a hydrogen donor and release O2 into the environment

banded iron formations

laminated sedimentary rocks; prominent feature in geological record. from about 2.5 bya indicate the release of O2 into the oceans

How did the presence of O2 impact life on Earth?

O2 is toxic to organisms who don't have protective organisms so many died as O2 levels built up.
- creates an oxidizing environment, which can destroy precious reduced organic molecules
- some anaerobic organisms survive only in environments with little o

ozone layer

the formation of the ozone layer soon after oxygenation of the atmosphere provided protection from UV radiation and allowed life to expand to regions at and near the Earth's surface

endosymbiotic theory

model for how at least some of the eukaryotic cell organelles came to exist

Basis for the divisions of Earth's history

1. divisions are based on major changes in types of organisms found in fossil record
2. many of the transitions are marked by major extinction events because organisms apparently died off over a short period of time and are erased from the fossil record
3

Precambrian Time

-from 4.6 bya to 542 million years ago
- Snowball Earth?? 800 mya
- 635 mya
- ended with Ediacaran Period

Ediacaran Period

- Within Precambrian Time
- 635-542 mya
- widely recognized as having the oldest animal fossils

Paleozoic Era

- 542 - 251 mya
- Divided into the Cambrian Period, Ordovician Period, Silurian Period, Devonian Period, Carboniferous Period, and Permian Period

Cambrian Period

- 542-488 mya
- Cambrian explosion
- all contemporary animal phyla are represented in Cambrian fossils, as well as many extinct groups
- biggest expansion in diversity found in the fossil record
- Burgess shale

Cambrian explosion

fossils of multicellular organisms are abundant in this period

Burgess Shale

most examples found in Cambrian fossils

Ordovician Period

- 488-444 mya
- abundant numbers of diversification of trilobites, brachiopods, and molluscs
- first coral reefs
- first terrestrial plants
- ended in mass extinction event ( 1st of big five )

1st Mass Extinction: Ordovician

Likely due to an ice age, perhaps in conjunction with a gamma ray burst. It decimated the trilobites and brachiopods, along with other groups of marine organisms

Silurian Period

- 444-416 mya
- first vascular plants
- first true terrestrial animals

Devonian Period

- 416-359 mya
- jawed fishes, amphibians, insects, and vascular plants first appear
- jawed fishes diversify and dominate the seas and vascular plants diversify and dominate the land
- ended in mass extinction event 2

2nd mass extinction event

ended the Devonian Period

Carboniferous Period

- 359-299 mya
- reptiles first appear
- amphibians diversify and dominate terrestrial carnivores (Age of Amphibians)
- most of today's coral deposits are the remains of organisms that lived in this period

Permian Period

- 299-251 mya
- by the end of this period, the continents have merged as the Pangea supercontinent
- era ended with a mass extinction event 3

3rd mass extinction

- the largest mass extinction on record
- more than 90% of the marine species and 70% of land vertebrates that are in the fossil record at the end of the Permian never appear in the fossil record again
- apparently took place in a time span of only a few

Mesozoic Era

- 251-65 mya
- diversification and dominance by reptiles (whole era is often called Age of Reptiles)
- Includes the periods Triassic, Jurassic, and Cretaceous

Triassic Period

- 250-200 mya
- dinosaurs and mammals first appear
-gymnosperms are the dominant land plants
- ended with a mass extinction event 4

Jurassic Period

- 200- 146 mya
- dinosaurs dominate the land
- birds evolve from a dinosaur lineage

Cretaceous Period

- 146-65 mya
- flowering plants evolved early and diversified quickly
- many animals appear to have coevolved with flowering plants

Coevolution

Process by which two species evolve in response to changes in each other

5th mass extinction

- dinosaurs eventually all died out
- most gymnosperms also died out, as did many marine organisms
- evidence points to the impact of a large extraterrestrial body as a likely cause of the extinction event
- iridium layers deposits from tsunamis around th

Chicxulub Crater

proposed meteorite impact crater, centered on chixiclub on the yucatan of mexico, discovered in 1950s at the time it was interpreted,

Cenozoic Era

- 65 mya - present
- usually called the Age of Mammals, but birds, insects, and flowering plants have also undergone massive diversification and have achieved some dominance
- divided into two periods: Paleogene and Neogene

Paleogene Period

- 65-23 mya
- radiation of mammals, bird, and pollinating insects; origin of many primate groups

Neogene Period

- 23 mya - present
- earliest direct human ancestors; appearance of bipedal human ancestors

current mass extinction event

mostly caused by humans, and we are in one right now