Tpr Biology

Front 1

Define thermodynamics.

Back 1

Conversion of heat to energy. Only concerned with final destination, not pathways.

Front 2

What is the 1st Law of Thermodynamics?

Back 2

Universal energy is constant.

Front 3

What is the 2nd Law of Thermodynamics?

Back 3

Energy transformation increases universal disorder (entropy, ΔS).

Front 4

What is the equation for Gibbs Free Energy?

Back 4

ΔG=ΔH-TΔS

Front 5

What is the equation for enthalpy?

Back 5

ΔH-ΔE-PΔV

Front 6

What does a positive ΔG mean? Negative?

Back 6

If (+) then non-spontaneous, unfavorable, endergonic, exothermic reaction.
If (-) then spontaneous, favorable, exergonic, exothermic reaction.

Front 7

What happens in Gibbs Free Energy is in equilibrium?

Back 7

ΔG=ΔG^0'+RTln(K) where Keq=[products]/[reactants]

Reactants and products turnover at the same rate but concentration is constant.

Equilibrium tends towards to lowest energy state.

Front 8

Define kinetics.

Back 8

Study of the reaction rate after Ea has been reached.

Front 9

Define catalysts.

Back 9

Increase the reaction rate by reducing Ea without changing ΔG

Stabilizes the transition state (TS).

Not consumed or changing in the reaction.

Front 10

Name a common type of catalyst.

Back 10

Enzymes.

Front 11

What are proteases?

Back 11

Protein-cleaving enzymes with a serine reside in the active site whose -OH acts as a nucleophile to attract polypeptide residues.

Front 12

Name and define the four types of enzyme activity.

Back 12

• Covalent modification: proteins may have different groups covalently attached that regulate their activity• Proteolytic cleavage: many enzymes are synthesized in inactive forms (zymogens) activated by cleavage by a protease• Associations: some enzymes have catalytic activity in one polypeptide subunit regulated by association with a separate regulatory subunit (constitutive activity)• Allosteric regulation: binding of small molecules to certain sites on an enzyme that aren't the active site (usually noncovalent and reversibly bound)

Front 13

Define negative feedback.

Back 13

An end-product doesn't shut off an enzyme earlier in the pathway.

Front 14

Define positive feedback.

Back 14

Enzyme is stimulated by its substrate or a molecule that synthesizes the substrate.

Front 15

Define enzyme kinetics.

Back 15

Study of the rate of product formation from substrates in the presence of enzymes

Front 16

What is the reaction rate?

Back 16

Reaction rate (V) is the amount of product formed per unit time and is directly proportional to substrate.

Front 17

Define saturated enzymes.

Back 17

Substrate levels are so high the reaction doesn't increase when more is added.

Front 18

Define cooperativity and explain the graph.

Back 18

Substrate binding to a macromolecule promotes substrate binding.

Tense state (bottom, substrate affinity is low), relaxed state (slope, substrate impacts rate) & saturated (Vmax, top)

Front 19

Define competitive and noncompetitive inhibitors.

Back 19

Competitive: inhibitor binds at the active site, competes with substrate. Adding substrate overcomes inhibition (Vmax doesn't change, Km increases)

Noncompetitive: inhibitor binds at allosteric site, doesn't compete with substrate. (Lowers Vmax, Km doesn't change)

Front 20

Explain oxidation and reduction.

Back 20

Oxidization: "bind to oxygen" when oxygen is added and hydrogen or electrons are removed

Reduction: "remove oxygen" when hydrogen or electrons are added and oxygen is removed

Front 21

Define catabolism and anabolism.

Back 21

Catabolism: breakdown of molecules.

Anabolism: formation of molecules.

Front 22

Explain oxidative catabolism.

Back 22

Extracts energy from glucose includes glycolysis, PDC, Krebs cycle, and electron transport.

Front 23

What is glycolysis and what is the yield?

Back 23

Glucose is split into two pyruvic acids aerobically in the cytoplasm. Glycerol phosphate shuttles NADH to inner mitochondria matrix.

Yields: -2 ATP, 4 ATP, 2 NADH (3 ATP in eukaryotes, 5 in prokaryotes)

Front 24

What does the pyruvate dehydrogenase complex (PDC) do and what does this yield?

Back 24

Functions in mitochondrial matrix to convert pyruvate to acetyl CoA and generate 2 NADH (5 ATP).

Front 25

What happens in the Krebs cycle and what does it yield?

Back 25

Takes the 2C acetyl from acetyl CoA, combines with oxaloacetate and releases 2 CO2.

Yields: 6 NADH (15 ATP), 2 FADH2 (3 ATP) and 2 GTP (2 ATP)

Front 26

What is electron transport and where does it occur?

Back 26

NADH and FADH2 are oxidized in the inner mitochondrial matrix, ends with the reduction of oxygen and the creation of a proton gradient.

Front 27

What is cellular respiration and how much ATP is produced?

Back 27

Oxidation of carbohydrates, reduction of electron carriers, and generation of ATP.

30 ATP in eukaryotes, 32 in prokaryotes

Front 28

Define fermentation.

Back 28

In anaerobic conditions, regenerates NAD+ by using pyruvate to accept high energy electrons (i.e. ethanol and lactate) to allow glycolysis to continue

Front 29

What is the appearance of structural and catalyst proteins?

Back 29

Structural are fibrous (i.e. collagen) and catalyst are spherical (i.e. enzymes)

Front 30

DDefine cofactors.

Back 30

Needed for enzyme's function but don't interact

Front 31

Define prosthetic group.

Back 31

Nonprotein molecule covalently bound to an enzyme at the active site (i.e. vitamins)

Front 32

How do unfavorable reactions occur?

Back 32

By coupling them to favorable reaction.