Bio Ch 6

Front 1

Kinetic & Potential Energy

Back 1

Kinetic- energy of motion
Potential- capacity to do work owing to position or state.

Front 2

Heat

Back 2

KE of randomly moving particles. Can't perform work.

Front 3

Heat energy

Back 3

Flows from an object with a her temperature to one with a lower. This can perform work.

Front 4

Entropy (S)

Back 4

- Measure of disorder or randomness
- usuable energy has low (S)
- disorganized energy- high (S).

Front 5

Metabolism

Back 5

- Sum of all the chemical activities taking place in an organism.
- Consists of many intersecting series of chemical reactions or pathways

Front 6

Types of metabolism

Back 6

Anabolism & catabolism

Front 7

Anabolism

Back 7

-Includes the various pathways in which complex molecules are synthesized from simpler substances, such as the linking of amino acids to form proteins.

Front 8

Catabolism

Back 8

Includes the pathways in which larger molecules are broken down into smaller ones, such as the degradation of starch to form monosaccharides.
-Involves an overall release of energy, which powers anabolic pathways.

Front 9

Enthalpy (H)

Back 9

-Total potential energy of a system.
-Referred to as the heat content of the system.

Front 10

Free Energy (G)

Back 10

Amt. of energy available to do work under the conditions of a biochemist reaction.
-only energy to do cell work.

Front 11

1st law of thermodynamics

Back 11

Energy cannot be created or destroyed but can be transferred or converted from one form to another.

Front 12

2nd law of thermodynamics

Back 12

When energy is converted from one form to another, some usuable energy is converted into heat that disperses into the surrondings.

Front 13

Relationship b/t enthalpy, free energy, and entropy.

Back 13

<>G= <>H - T<>S

Front 14

EQN= entropy increases, free energy decreases.

Back 14

G= H- TS

Front 15

Exergonic rcns

Back 15

rcns that proceed w/o an input of energy from outside. "Downhill".negative G

Front 16

Endergonic rcn

Back 16

rcn where there is a gain in free energy. require an input of energy. uphill rcns. positive <>G.

Front 17

Coupled rcns

Back 17

the thermodynamically favorable exergonic rcn provides the energy required to frive the thermodynamically unfavorable endergonic rcn.

Front 18

ATP stands for?

Back 18

Adenosine triphosphate

Front 19

ATP

Back 19

Holds readily available energy for short periods. ATP is the energy currency of the cell.

Front 20

ATP's structure

Back 20

ATP is a nucleotide consisting of three parts: adenine (nitrogen base); ribose (5-C sugar); 3 phosphate groups

Front 21

ADP

Back 21

adenosine diphosphate. when terminal phosphate is removed.

Front 22

Pi

Back 22

inorganic phosphate. hi-energy of ATP.

Front 23

phosphorylation rcn

Back 23

phosphate group is transferred to some other compound. That compound becomes energized.

Front 24

Link b/t exergonic & endergonic

Back 24

ATP occupies an intermediate position. exergonic-catabolic, endergonic-anabolic.

Front 25

oxidationa & reduction

Back 25

oxidation-substances lose e-
reduction- substance gains e-

-both called redox rcns b/c they occur simultaneously.
-The substance that becomes oxidized, gives up electrons (energy), the substance that reduces, receives energy as it gains electrons.

Front 26

electrons & free energy

Back 26

an electron loses free energy as it is transferred from one acceptor to the next.

Front 27

NAD+

Back 27

acceptor molecule. when reduced, it stores large amts. of free energy, and becomes NADH.

Front 28

NADP & FAD

Back 28

NUcleotides when accept H+ atoms become: NADPH & FADH2

Front 29

Cytochromes

Back 29

proteins that accept e-, and not H+ atoms.

Front 30

Energy of activation

Back 30

(Ea) energy required to break existing bonds and begin the reaction.

Front 31

enzyme & Ea

Back 31

Enzymes lower Ea, but no effect on the overall free energy change. speed up rcn rates.

Front 32

Enzyme substrate complex

Back 32

Substrate binds to the enzyme at the active site forming an enzyme-substrate complex.

Front 33

Induced fit

Back 33

The binding causes a change in the enzymes's shape. The change in shape lowers Ea.

Front 34

Cofactors

Back 34

Enzyme "helpers". Nonprotein substances.

Front 35

Kinds of cofactors

Back 35

(1) Inorganic ions. Mg, Ca
(2) Nonpolypeptide organic molecules. Coenzymes. vitamins.

Front 36

Optimal temperature

Back 36

Rate of rcn is fastest at a certain temp. Hi temp denature enzymes. H+ bonds break. activity not regained when enzyme is cooled.

Front 37

Optimal pH

Back 37

Changes in charge affect the ionic bonds that contribute to tertiary & quartenary, thus changing shape.

Front 38

Metabolic pathway

Back 38

When the product of one ES complex becomes the substrate for another. A->B->C

Front 39

How do cells regulate enzyme activity?

Back 39

- by controlling amt. of enzyme produced
- by controlling amt. of substrate produced.
- feedback inhibiton

Front 40

Feedback inhibition

Back 40

The formation of a product inhibits an earlier rcn in the sequence

Front 41

Allosteric enzymes

Back 41

Have an allosteric site, which allosteric regulators bind to.

Front 42

Reversible inhibtion

Back 42

when an inhibitor forms weak chemical bonds with the enzyme. Can be competitive or non-competitive

Front 43

Competitive inhibition

Back 43

the inhibitor competes with the substrate for binding to the active site. Occupies the site temporarily, and doesn't damage the enzyme.

Front 44

Non-competitive inhibtion

Back 44

the inhibitor bindsw w/ th enzyme at a site other than the active site. This inactivates the enzyme by altering its shape.

Front 45

Irreversible inhibition

Back 45

an inhibitor permanetly inactivates the enzyme when it combines with one of its functional groups.

Front 46

allosteric inhibtion

Back 46

non-competitive inhibition

Front 47

poison

Back 47

ireeversible enzyme inhibitors