AP Bio Test Review

Solvent

Substance that can dissolve other molecules known as solutes

polar definition

Nuetral/uncharged, but has an asymmetric internal distribution of charge, leading to partially positive and partially negative regions

How does surface tension work

Exposed to air on one side, will have fewer neighboring water molecules to bond with and will form stronger bonds with the neighbors they do have

Why is water less dense as ice

water molecules form a crystal structure maintained by H+ bonds - so water molecules are pushed farther apart than in liquid water

Evaporative cooling

As molecules evaporate, they absorb heat from the surface they evaporate from

What bonds keep Oxygen and Hydrogen in a water molecule together

Polar covalent

What bonds keep two water molecules together

Hydrogen

Electronegative

Affinity for attracting electrons

4 elements common to all living organisms

O, C, H, N

Cations

Positive ions formed by an electron loss

Anions

negative ions formed by electron gain

Polar covalent vs non polar covalent

Polar: electrons shared unequally and closer to one atom

Nonpolar: electrons shared equally

Why are strong and weak bonds necessary in DNA

Strong hold building blocks of DNA strand together, weak hold DNA helix strands together

Dehydration synthesis

polymers formed from monomers. Monomer forms covalent bond to another monomer, releasing a water molecule

Hydrolysis

Monomer formed from polymer. Bond broken by adding water

Carb function

quick/short term energy

Lipid function

long term energy, make up biological membranes

Protein fuctions

Cell structure, send chemical signals, speed up chemical reactions, etc.

What bonds do amino acids form

Covalent

How does the DNA —> RNA —> Protein process work

genes encode sequence of amino acids for particular proteins. RNA copy of gene made (mRNA) which serves as a messenger between DNA and ribosomes (which read mRNA sequence in groups of three (codons) adding amino acid for each codon

tRNA function

Bring amino acids to ribosome for protein synthesis

Nucleotide parts

nitrogenous base (ATCG), 5 carbon sugar, and phosphate group

what does rRNA do

helps mRNA bind in right spot so sequence info can be read out, can also accelerate chemical reactions

What elements does DNA have

Carbon, oxygen, hydrogen, nitrogen, phosphorus

Do proteins have sulfur or phosphorus

Sulfur, no phosphorus

Protein structures

Primary: linear order of amino acids, peptide bonds

Secondary: interactions of the peptide backbones, beta pleated sheets and alpha helices, hydrogen bonds

Tertiary: side chain interactions, 3D, hydrophobic interactions and ionic bonds

Quaternary: multiple peptide chains

Saturated vs unsaturated

Saturated : no double bonds, packed tightly, solid at room temp, can form tighter bonds because there isn’t a link in one leg

Unaturated: double bonds, no tight packing, liquid at room temp, maintain fluidity in membrane

Equation to determine how many water molecules were released during dehydration synthesis

n-1

So if 20 amino acids formed polypeptides, then 19 water molecules were released.

cytosol vs cytoplasm

Cytosol is what is outside of the organelles, cytoplasm refers to what is outside and inside of the cell organelles

if a cell has a lower water potential than the solution it is in, which direction will the water move

Into the cell

Rough ER vs Smooth ER

Rough: protein and lipid synthesis: proteins fold and modify, send to golgi or secreted or incorporated into cell membrane

Smooth: synthesis of carbs, lipids and steroid hormones, detoxifies

Golgi function

Lipids and proteins from ER sorted, packaged, and tagged so they end up in right place.

Lysosome function (only in animal cells)

digestive enzymes and organelle recycling facility - breaks down old/unecessary structures so molecules can be reused, some vesicles that leave the golgi go to lysosome, can digest foreign particles brought into cell (pathogens)

Vacuoles

Storage for water and wastes, isolates hazardous materials and has enzymes that can break down macromolecules, when its full of water it keeps shape of cell

Why is plasma membrane fluid

So things can go in/out and it can rearrange to account for that

Carb function in plasma membrane

Forms distinctive cellular markers that allow cells to recognize each other - important in immune system

Cholesterol function in membrane

minimizes effects of temperature on fluidity

3 factors that affect membrane fluidity

temperature, cholesterol, saturated and unsaturated fatty acids

Which molecules can pass and which cant through the membrane

pass: small non polar (gases), small polar (H20)

need transport protein: large polar(glucose), large non polar(carbon rings), ions (Na+)

Hypertonic vs hypotonic

Hyper: solution has a higher solute concentration than the cell - cell shrinks

Hypo: solution has lower solute concentration than the cell - cell swells

Water potential: ionization constant - when is it -1 and when is it -2

-1 for molecules that don’t dissolve (ex. sugar), -2 for molecules that do dissolve (ex. NaCl)

Light Reaction

Light energy converted into ATP/NADPH using e- from H20

Calvin Cycle (light independent reaction)

Takes newly made ATP to power chem reactions, converting CO2 and H from H20 into glucose

Where does light dependent reactions happen? Calvin Cycle?

Light dependent: thylakoids

Calvin: stroma

light reaction products and reactants

Reactants: light energy, water

Products: ATP, NADHP, oxygen

Photosystem 2 and photosystem 1 function

2: provide energy to create ATP

1: provide energy to create NADPH

Calvin Cycle reactants and products

reactants: co2, ATP, nadph

products: glucose, ADP, NADP

3 phases of Calvin cycle

carbon fixation, reduction, regenerationC

what happens during carbon fixation in Calvin cycle

CO2 is “fixed” into a carb by the enzyme Rubisco

what happens in reduction of calvin cycle

6ATP and 6NADPH used to make 6G3P molecules. ADP and NADP go back to light reactions to be reused and reenergized

What happens in regeneration of Calvin cycle

1 G3P leaves cycle to make glucose, other 5 used to regenerate RuBP so another CO2 can be “fixed” into a carb"

Cellular respiration products and reactants

R: glucose, oxygen

P: CO2, water, ATP

4 steps of cellular respiration

Glycolysis, pyruvate oxidation, Krebs/citric acid cycle, ETC

Where does glycolysis occur

Outside of mitochondria in cytoplasm

What does glycolysis do

Partially oxidizes glucose to 2 pyruvates, gaining 2 ATP and 2 NADH

Why does glycolysis need to break down glucose to pyruvates

To fit through the mitochondrial membrane

2 steps of glycolysis

Energy investment: endergonic, glucose phosphorylated, rearranged, and split into 2 G3P molecules

Energy payoff: Exergonic, G3P gives H to NAD+, G3P broken down into pyruvate

Fermentation (glycolysis without O2)

Keeps glycolysis going by regenerating NAD+, occurs in cytosol, no oxygen needed, produces ATP for energy

Respiration (glycolysis with O2)

Occurs in mitochondria, oxygen required, produces CO2, H2O, and up to 32 ATP

Lactic Acid fermentation

Pyruvate —> lactate , NAD+ is regenerated so glycolysis can occur again which has a net gain of 2 ATP

Pyruvate Oxidation in cellular respiration

Pyruvate enters mitochondrial matrix. Pyruvate —> acetyl CoA

Krebs/citric acid cycle

occurs in mitochondrial matrix, Acetyl CoA —> citrate —> many reactions—>Co2 and NADH and FADH2 released

Net gain: 2 ATP, electron carriers - NADH + FADH2

Where does ETC occur

Along the Cristae in the inner membrane of mitochondria

How does ETC work

H+ ions pumped across inner mitochondrial membrane through protein pumps to create an H+ gradient. At end H+ diffuse through ATP synthase (ADP—> ATP). O2 is final electron acceptor in the form of H2)

Does the inside or outside of mitochondrial matrix have more H+

Outside has more H+