chapter eight part one

Question 1

metabolism

Answer 1

the totality of an organism’s chemical reactions

Question 2

metabolic pathway

Answer 2

where a specific molecule is altered in a series of define steps, resulting in a certain product
- each step catalyzed by certain enzyme

Question 3

catabolic pathways

Answer 3

degradative process (breakdown)
- ex. cellular respiration

Question 4

anabolic pathways

Answer 4

building complex molecules (biosynthetic)
- ex. synthesis of protein from amino acids

Question 5

bioenergetics

Answer 5

the study of how energy flows through living organisms

Question 6

energy sources

Answer 6

ATP, gradient, sunlight, reduced molecule energy (glucose)

Question 7

why ATP?

Answer 7

• same amount of energy as other nucleotides
• God gave it

Question 8

types of energy

Answer 8

kinetic, heat/thermal, potential, chemical

Question 9

energy

Answer 9

capacity to cause change

Question 10

kinetic energy

Answer 10

energy associated with relative motion of objects

Question 11

heat/thermal energy

Answer 11

kinetic energy associated with random movement of molecules

Question 12

heat

Answer 12

thermal energy in transfer from one object to another

Question 13

potential energy

Answer 13

energy possessed because of location and structure

Question 14

chemical energy

Answer 14

potential energy available for release in a chemical reaction

Question 15

thermodynamics

Answer 15

study of energy transformations that occur in a collection

Question 16

First Law of Thermodynamics

Answer 16

energy can be transferred and transformed, not created or destroyed
- energy is constant

Question 17

Second Law of Thermodynamics

Answer 17

energy transfer increases entropy

Question 18

entropy

Answer 18

measure of disorder and randomness

Question 19

free energy

Answer 19

energy that is available for work (G)

Question 20

equation for free energy

Answer 20

delta G = delta H - T(delta S)
- total energy minus disorder

Question 21

delta G

Answer 21

change in free energy (Gibbs)

Question 22

T

Answer 22

absolute temperature (K)

Question 23

delta S

Answer 23

change in system’s entropy

Question 24

delta H

Answer 24

change in system’s enthalpy (total energy)

Question 25

does free energy increase or decrease in a spontaneous process?

Answer 25

decrease

Question 26

spontaneous process

Answer 26

energetically favorable, occurs without input of energy

Question 27

a highly ordered system is

Answer 27

unstable

Question 28

in a spontaneous reaction, delta G has a _______ value

Answer 28

negative (decrease in free energy)

Question 29

at equilibrium, delta G =

Answer 29

0 (no net change in system)

Question 30

exergonic reaction

Answer 30

releases energy - G is negative - occur spontaneously

Question 31

endergonic reaction

Answer 31

needs energy - G is positive - non spontaneous

Question 32

metabolic disequilibrium

Answer 32

defining feature of life, organisms never at equilibrium

Question 33

cell is dead at

Answer 33

metabolic equilibrium

Question 34

what does breaking bonds require?

Answer 34

energy

Question 35

if chemical process is exergonic, then reverse process is

Answer 35

endergonic

Question 36

3 types of cellular work

Answer 36

1. chemical 2. transport 3. mechanical

Question 37

chemical cellular work

Answer 37

pushing of endergonic reactions, synthesis of polymers from monomers

Question 38

transport cellular work

Answer 38

pumping of substances across membranes against direction of spontaneous movement

Question 39

mechanical cellular work

Answer 39

beating of cilia, contraction of muscle cells, movement of chromosomes

Question 40

energy coupling

Answer 40

use of exergonic process to drive endergonic one - ATP driven

Question 41

ATP composition

Answer 41

ribose + adenine + 3 phosphate groups

Question 42

hydrolysis

Answer 42

addition of water molecule to break terminal phosphate bond - ATP to ADP - exergonic reaction, releases 7.3 kcal/mol hydrolyzed

Question 43

kcal/mol

Answer 43

delta G = 7.3 kcal/mol (standard conditions for ATP)

Question 44

ATP + H20 =

Answer 44

ADP + Pi + energy (inorganic phosphate)

Question 45

where does regeneration of ATP occur?

Answer 45

mitochondria

Question 46

phosphorylation of ADP

Answer 46

additionally of phosphate to ADP - energy comes from catabolism (exergonic) in cell

Question 47

catalyst

Answer 47

chemical agent that speeds up reactions without being consumed

Question 48

enzymes

Answer 48

macromolecule that acts as a catalyst

Question 49

activation energy

Answer 49

initial energy of investment for starting a reaction - contort reactant molecules so bonds break

Question 50

what can an enzyme not change?

Answer 50

delta G for reaction or make endergonic reaction exergonic

Question 51

substrate

Answer 51

reactant an enzyme acts on

Question 52

enzyme-substrate complex

Answer 52

when enzyme binds to substrate - while bound, substrate converted to product

Question 53

active site

Answer 53

allows binding of substrate

Question 54

induced fit

Answer 54

active site clasps to substrate

Question 55

what type of bonds connect the substrate and enzyme?

Answer 55

hydrogen and ionic

Question 56

how catalysis occurs in enzyme's active site

Answer 56

- R groups of amino acids catalyze conversion of substrate to product 1. substrate fits into active site 2. substances held by weak interactions 3. E(A) lowered, reaction speeds up 4. substrates converted to products and released

Question 57

factors on enzyme activity

Answer 57

temperature, pH, cofactors, coenzymes

Question 58

temperature and enzymes

Answer 58

rate of reaction increases w/ increasing temperature up to point, above that hydrogen/ionic bonds disrupted and enzyme denatures

Question 59

pH and enzymes

Answer 59

6-8, but some exceptions

Question 60

cofactors

Answer 60

non-protein helpers of catalytic activity - inorganic (metal ions)

Question 61

coenzyme

Answer 61

organic molecule that helps catalytic activity

Question 62

when can an endergonic reaction be spontaneous?

Answer 62

when it is coupled with an exergonic reaction