BSC 1010 Unit 1 Final Review

Evolution

Unity and diversity of life explained by the theory of evolution

Darwin's "Natural Selection

1. Populations grow faster than food supplies = a struggle to . survive.2. Offspring have variations; favorable traits will be passed on for survival.3. "survival" of the fittest

Artificial Selection

Humans pick and choose what genes will be passed on ex. selective breeding in dogs

Biological Domains

Bacteria, Archaea, and Eukaryotes (BAE)

Prokaryotes

Unicellular, lack membrane bound organelles and a nucleusinclude: Bacteria and Archaea (extremophiles)

Eukaryotes

Include membrane bound organelles, can be unicellular or mulitcellular

Biological Scale

Biosphere, Ecosystem, Community, Population, Organism, Organ System, Organ, Tissue, Molecule, Atom

Reductionism approach

Breaking components down into simpler parts

Systems approach

Holistic objective of understanding how all parts of a system work together to produce emerging properties

Observation/Theory-based science

Theory: explains a great diversity of observations and is supported by a great body of science

Hypothesis-based science

Educated guess; tentative explanation

Scientific Method

ObservationQuestionHypothesis/Prediction Experiment Analyze Make Conclusions

Atomic Mass

Protons + Neutrons (Neutrons can vary which are called isotopes)

Atomic Number

Number of protons*Usually determines what the element is

Ionic Bonding (molecules/compounds)

Charged ions are attracted to each other -Cation ion is the positive ion, donating e--Anion is negatively charged, gains e-

Covalent Bonding

Co-sharing of valence electrons, forming molecules.

Nonpolor Covalent Bonds

equal sharing of electrons e-

Polar Covalent bonds

allows one atom to 'hog' electrons and become slightly negative while other atom is slightly positive

Hydrogen Bonding

Hydrogens connected to oxygen or nitrogen form polar bondsboth very electronegative ex. DNA Base Pairs

Van Der Waals forces

A weak attractive force between atoms or nonpolar molecules caused by a temporary change arising from a brief shift of electrons ex. Lizards 'geko' pads help stick on walls and etc.

Electronegativity

influenced by an elements's density and fullness of a valence shell

Emergent Properties of Water

Based on hydrogen bonding between its polar covalent molecules 1. Cohesion: Adhesion and surface tension -Cohesion (like molecules) because of H bonding-Adhesion (unlike molecules)where water sticks to other substances like a droplet on a leaf-Surface tension extra strong due to cohesion. 2. Temp. moderation-Large bodies of water heat slowly and cool slowly and have a high specific heat capacity-Water phase changes: Large amount of energy to vaporize and large amount of energy to take away to freeze 3. Insulation -bc ice is less dense than water and can insulate objects from colder temperatures4. Water acts as a solvent -Solvent because of its polarity, can form hydration shells around each ion. Hydrophilic - water loving substance (polar or ionic), hydrophobic - water fearing substance(non-polar).

pH Balance

1 to 14 Acidic (1)-Neutral (7)-Basic (14)

Buffers

Resist pH changes ex. carbonic acid and bicarbonate ion maintain pH in body(Left to resist drop in pH) H2CO3 <-> HCO3- + H+( Right to resist rise in pH)

Carbon

-Can bond with up to 4 different atoms-can have single, double, or triple bonds

Isomers

Structural Isomers: same molecular formula but differ in 3-D shapeCis-trans (geometric) Isomers: different in functional groups around a double bond since a double bond does not allow for rotation

Functional Groups

chemically reactive groups of atoms within an organic molecule with specific chemical properties

-OH

Hydroxyl-alcohols

>C=O

Carbonyl-aldehyde and ketone

-COOH

Carboxylic acid

-NH2

Amino Acid

-SH

Sulfhydryl-forms bridges from cysteine amino acids

-PO4

Phosphate-ATP, and methyl

-CH3

methylating DNA to turn genes off (sometimes on)

Biological Molecules (CLPN)

1. Carbohydrates: sugars and starches (monosacrides: glucose and fructose, disaccrides: sucrose and maltose, polysaccrides: starch and cellulose)2. Lipids: fats and oils, steroids, phospholipids 3. Proteins: amino acids4. Nucleic Acids: DNA and RNA

Starch v. Cellulose

starch: stores energy, forms long chains of glucose that do NOT stick togethercellulose: is for strength, forms long chains of glucose that hydrogen bond together****Humans CAN digest starch, but not cellulose (Cows can though)

Dehydration synthesis v. Hydrolysis

monomers to polymers v. polymers to monomersWater removed to link monomers into a polymer; Water added to split polymer into monomers.

Triglycerides

Fats and oils, glycerol plus 3 fatty acids

Proteins

polyemrs of amino acids, 4 levels of structure 1. Primary: determined by DNA code2. Secondary: Beta-sheets or alpha-helix3. Tertiary: Disulfide, ionic bonding: hydrophobic core 4. Quaternary: interaction betwn 2+ proteins

Nucleic Acids

Differences between RNA and DNA