test 4 lec 20

Question 1

what does additivity helps

Answer 1

makes it possible to do work by coupling an energy yielding reaction to an energy spending one

Question 2

if delta G is pos

Answer 2

reaction will go in reverse

Question 3

what is delta S based on

Answer 3

number of states of system

Question 4

what represents the state of greatest entropy

Answer 4

the random distribution of molecules at uniform concentration

Question 5

if entropy increases then…

Answer 5

reactions in which a complex molecule is broken down to a greater number of smaller molecules increase entropy
+ delta S

Question 6

what does the delta G value of a reaction determines

Answer 6

how much energy is potentially available to do work under defined conditions

Question 7

many of the cell’s energy transfer reactions involve what

Answer 7

energy carriers

Question 8

electron donors are

Answer 8

reducing agents, donate electrons

Question 9

at the end of the series of oxidation-reduction transfers, the electrons are transferred to

Answer 9

a terminal electron acceptor

Question 10

rate of reaction is determined by

Answer 10

the activation energy

Question 11

what factors determine delta G

Answer 11

intrinsic properties of a reaction
concentrations of reactants and products
environmental factors

Question 12

what is different from NADH to ATP

Answer 12

carry two or three times as much energy as ATP

also donates and accepts electrons

Question 13

what is an allosteric site

Answer 13

found in enzyme with with catalytic site
regulatory site from the substrate binding site
alters conformation of enzyme increasing the rate of reaction

Question 14

who does catabolism provide energy for

Answer 14

anabolism

Question 15

what is needed in order to keep energy from releasing all at once and as heat

Answer 15

need to use steps to create energy release, smaller energy change

Question 16

what measures the heat released or absorbed during a reaction

Answer 16

calorimeter

Question 17

purpose of standard conditions for delta G

Answer 17

enable scientists to compare intrinsic properties of reactions

Question 18

what are the three different ways that ATP transfer energy to cell processes

Answer 18

hydrolysis releasing phosphate
hydrolysis releasing pyrophosphate
phosphorylation of an organic molecule

Question 19

what is entropy

Answer 19

a measure of the disorder or randomness of a system

Question 20

what is enthalpy

Answer 20

a measure of the heat energy in a system

Question 21

how does continual growth occur in a cell

Answer 21

a continual gain of energy and continual radiation of heat

Question 22

+ delta H

Answer 22

reactants absorb heat

Question 23

what are energy carriers

Answer 23

molecules that gain or release smalls amounts of energy in reversible reactions

Question 24

if molecular stability increases then…

Answer 24

reactants combine to form products with more stable bonds

- delta H

Question 25

• delta H

Answer 25

heat is released and provides energy

Question 26

delta S driven reactions depend on

Answer 26

temp

Question 27

why do different rxns use different energy carriers

Answer 27

different redox levels
different amounts of energy
regulation and specificity

Question 28

soma energy carriers also transfer what

Answer 28

electrons

Question 29

what are the standard conditions for delta G

Answer 29

298 K
1 atm
1 M

Question 30

to provide energy, a biochemical reaction must go

Answer 30

forward from reactants to products

Question 31

cells use energy for what

Answer 31

assemble simple, disordered molecules into complex, ordered forms

Question 32

what is anabolism

Answer 32

reactions that build complex biomolecules from smaller precursors
biosynthesis

Question 33

cell build order by spending the energy they gain through…

Answer 33

catabolism, lithotrophy, and phototrophy

Question 34

what are ex of energy carriers

Answer 34

ATP and NADH

Question 35

electron acceptors are

Answer 35

oxidizing agents, receives electrons

Question 36

if delta G is neg

Answer 36

process may go forward

Question 37

how do enzymes lower the activation energy

Answer 37

by bringing the substrates in proximity to one another and by correctly orienting them to react
catalytic site

Question 38

what is syntrophy

Answer 38

pairing of multiple species to achieve a chemical reaction that, carried out on its own, would be energetically unfavorable

Question 39

what does Delta H mean

Answer 39

the heat absorbed or released as reactants become products at constant pressure

Question 40

what are some characteristic of FAD

Answer 40

reduced by two electrons
two protons
donates two electron to an electron acceptor

Question 41

what is phosphorylation of an organic molecule

Answer 41

atp can transfer phosphate to -OH group of a molecule to activate it

Question 42

low to high concentration does what to entropy

Answer 42

decreases

Question 43

does the cell grow by gaining or losing energy

Answer 43

gaining

Question 44

what is entropy

Answer 44

measure of the disorder or randomness of a system

Question 45

what does delta S mean

Answer 45

change in entropy or disorder

Question 46

wha is a concentration gradient good for in a cell

Answer 46

across membrane can be used to store energy for the cell

Question 47

overall reduction of NAD+ consumes what

Answer 47

two hydrogen atoms to make NADH

Question 48

a reaction yields energy for the cell if

Answer 48

molecular stability increases

entropy increases

Question 49

what is catabolism

Answer 49

the breakdown of complex molecules into smaller ones

yield energy

Question 50

what is energy

Answer 50

the ability to do work

Question 51

ATP always forms a complex with

Answer 51

Mg2+

Question 52

as order increases, what happens to entropy

Answer 52

decreases