The tree in your backyard is home to two cardinals, a colony of ants, a wasp's nest (a colony of wasps), two squirrels, and millions of bacteria. Together, all of these organisms represent
a community
the ultiment source of enery in nearly all ecosysystems is
sunlight
A consumer eating a producer represents
a transfer of chemical nutrients and energy.
The formation of systems typically results in the appearance of novel characteristics called
emergent properties.
A scientist examining a group of cells under the microscope notices the presence of nuclei within these cells. Chemical tests reveal that each cell is photosynthetic and is surrounded by a wall composed of cellulose. These cells must come from an organism
Plantae.
Which one of the following statements is not consistent with Darwin's mechanism of natural selection?
Individual organisms exhibit genetic change during their life spans to better fit their environment.
A scientist performs a controlled experiment. This means that
two experiments are conducted, one differing from the other by only a single variable.
The nucleus of an atom contains
protons and neutrons.
Your instructor asks you to look into your microscope to see a prokaryotic cell. You will be looking for a cell that
has a membrane, but no nucleus.
Which of the following statements about radioactive isotopes is/are true?
can break chemical bonds and cause molecular damage in cells.
The smallest unit of an element is
an atom
A(n) __________ forms when two atoms share electrons.
covalent bond
In plants, the transport of water from roots to leaves against the force of gravity is possible due to this property of water:
Cohesion.
as ice melts...
hydrogen bonds are broken
A solute is
the substance that is dissolved in solution.
Compared to a solution of pH3, a solution of pH1 is
100 times more acidic
Which one of the following lists contains only polysaccharides?
cellulose, starch, and glycogen
A diet high in animal products may increase the risk for atherosclerosis. This is because
most animal fats are saturated and some animal products contain trans fats
Sucrose is formed
from two monosaccharides by dehydration synthesis.
DNA differs from RNA because DNA
contains thymine in place of uracil.
Glucose molecules are to starch as __________ are to proteins.
amino acids
Genetic information is encoded in the
sequence of nucleotides in DNA.
Light microscopes
use light and glass lenses to magnify an image.
A scanning electron microscope is used to study __________, whereas a transmission electron microscope is used to study __________.
cell surfaces . . . internal cell structures
Which of the following statements is consistent with the Cell Theory?
The cell is the basic structural and functional unity of life.
We can characterize the fluid mosaic model of a membrane as ____________ floating in a sea of ___________
proteins; lipid
Large, round cells can overcome surface area to volume problems by
becoming smaller, narrower or flatter.
As cell size increases, the
volume increases faster than the surface area.
Cells that lack a membrane-bound nucleus are __________ cells.
prokaryotic
The membranous compartmentalization of a cell
allows different metabolic processes to occur simultaneously.
If a biologist said that eukaryotic cells get their power from bacteria, they would be referring to
the mitochondria in our cells that may have originated as endosymbiotic bacteria.
Long fibers of DNA and protein are called a
chromatin.
Smooth endoplasmic reticulum
stores calcium ions in muscle cells.
Secretory proteins are
released from the cell through the plasma membrane.
The Golgi apparatus
stores, modifies, and packages proteins.
Contractile vacuoles
prevent cells from bursting as a result of the influx of excess water.
Cilia differ from flagella in that
more numerous and shorter than flagella.
Plants with rigid cell walls are unable to do which process?
phagoctyosis
Which of the following cell structures is not associated with the breakdown of harmful substances or substances that are no longer needed by the cell?
mitochondria
Small, nonpolar, hydrophobic molecules such as fatty acids
easily pass through a membrane's lipid bilayer.
Diffusion does not require the cell to expend ATP. Therefore, diffusion is considered a type of
passive transport
Osmosis can be defined as
the diffusion of water across a membrane.
what would happen if you placed cells in a hypotonic solution
cells would swell.
A cell that has neither a net gain nor a net lose of water when it is immersed in a solution is
isotonic to its environment
The act of a white blood cell engulfing a bacterium is
phagocytosis.
Phagocytosis is to eating as pinocytosis is to
drinking
According to __________, energy cannot be created or destroyed.
the first law of thermodynamics
Which one of the following processes is endergonic?
the synthesis of glucose from carbon dioxide and water
Anything that prevents ATP formation will most likely
result in cell death
Which one of the following is true about the ATP molecule?
It contains adenine.
When an enzyme catalyzes a reaction,
it lowers the activation energy of the reaction.
Which of the following is a coenzyme?
Vitamin B6
Bacterial production of the enzymes needed for the synthesis of the amino acid tryptophan declines with increasing levels of tryptophan and increases as tryptophan levels decline. This is an example of
feedback inhibition
The second law of thermodynamics states that____________.
energy tends to become increasingly dispersed and unusable.
The active site of an enzyme
is a groove or crevice on the structure of the enzyme.
The term anaerobic means
without O2.
The processes of photosynthesis and cellular respiration are complementary. During these energy conversions, some energy is
lost in the form of heat
During cellular respiration, the energy in glucose
is carried by electrons
Oxidation is the __________, and reduction is the __________.
loss of electrons; gain of electrons
Pyruvate
forms at the end of glycolysis.
Bacteria that are unable to survive in the presence of oxygen are called
strict anaerobes
Muscle soreness associated with strenuous exercise is at least partly due to
the presence of lactic acid produced during fermentation in muscle cells.
The terms "cristae" and "matrix" are associated with which cellular function(s)?
Krebs cycle and oxidative phosphorylation
Which of the following statements about glycolysis is correct?
production of pyruvate and occurs in the cytoplasm.
During respiration, the greatest amount of ATP is produced during
oxidative phosphorylation.
The location of the electron transport system in eukaryotic cells is
on the inner membrane of the mitochondria.
The oxygen we breathe in is needed for the process of respiration. Which of the following is the major role of oxygen in respiration?
Oxygen is the final electron acceptor at the end of the electron transfer chain.
The term "phosphorylation" refers to the
transfer of a phosphate to a substrate - like ADP.
Actinosphenia elegans is a unicellular, photosynthetic, eukaryotic organism. To which domain does it belong?
Eukarya
ALL protists possess _____________.
nuclei
Which of the following domains is NOT prokaryotic?
Eukarya
Which one of the following statements is most clearly inductively derived?
If any animals observed require organic molecules as nutrients, then it can be concluded that all animals require organic molecules as nutrients.
At which point is an investigator most likely to use deductive reasoning?
in establishing a test of a hypothesis