Chapter 13

Question 1

Catabolism

Answer 1

breakdown of complex molecules into smaller ones

Question 2

anabolism

Answer 2

reactions that build cells

Question 3

Catabolism provides energy for

Answer 3

anabolism. some energy is released as heat.

Question 4

Metabolism

Answer 4

all chemical reactions in an organism

• Balance b/w catabolism and anabolism

Question 5

Entropy

Answer 5

measure of randomness in a system

Question 6

Cells use energy to assemble

Answer 6

disordered molecules into ordered ones.

Question 7

Gibbs free energy change (ΔG)

Answer 7

how much energy is available to do work. Negative ΔG – reaction is favorable

Question 8

ΔG=ΔH-TΔS

Answer 8

ΔH = change in enthalpy
• Heat absorbed/released as reactants become products
• ΔS = change in entropy
• More ordered = lower entropy

Question 9

Excess reactants over products

Answer 9

more negative ΔG

Question 10

environ factors that change ΔS and ΔG

Answer 10

• Temperature, pressure, ionic strength

Question 11

Standard reaction conditions

Answer 11

• Temperature 298K, Pressure 1 atm, concentration 1M

Question 12

accounts for concentration

ΔG=

Answer 12

ΔG° +RT lnQ
• Q – reaction quotient
• R – gas constant
• T – temperature in K

Question 13

A+B ⟷C+D
Q=?
if products=reactants
if products < reactants

Answer 13

Q= C D/A B
If products = reactants, Q = 1; ln(1) = 0; standard conditions
If products < reactants, Q < 1; ln(<1) = negative number
temp can change Q

Question 14

Cells often break down reactions

Answer 14

into several steps

Question 15

Cells need energy carriers to transfer energy between reactions
energy carriers are

Answer 15

molecules that gain/release small amounts of energy in reversible reactions

Question 16

atp is made by

Answer 16

phosphorylating ADP. atp is a medium energy carrier.

• Energy carried in phosphate bonds

Question 17

three ways of transferring energy

Answer 17

1. Hydrolysis releasing phosphate (ATP–>ADP)
2. Hydrolysis releasing pyrophosphate (PPi)
3. Phosphorylation of an organic molecule
   • ATP can transfer its phosphate to hydroxyl group of another molecule (e.g. glucose)

Question 18

Electron acceptor

Answer 18

molecule that accepts electrons

Question 19

Nicotinamide adenine dinucleotide (NAD)

Answer 19

• NADH – reduced

* NAD+ - oxidized

Question 20

Flavin adenine dinucleotide

Answer 20

• FADH2 – reduced
• FAD – oxidized
• Weaker electron donor than NADH

Question 21

Activation energy (Ea)

Answer 21

determines rate of reaction

input energy needed to generate the high energy transition state

Question 22

catalyst

Answer 22

lowers Ea, isnt consumed.

Question 23

Carbohydrates

Answer 23

sugars, polysaccharides

Question 24

lipids

Answer 24

milk, animal fats, nuts

• Broken down to glycerol and fatty acids ->acetate (TCA)

Question 25

peptides

Answer 25

– proteins | • Deamination to produce carboxylic acid (TCA)

Question 26

aromatic compounds

Answer 26

lignin | • Broken down to acetate (TCA)

Question 27

fermentation

Answer 27

all e- from organic substrates are put back onto organic products • No terminal e- acceptor

Question 28

respiration

Answer 28

e- removed are transferred to inorganic electron acceptor | • Oxygen, nitrate (anaerobic respiration)

Question 29

photoheterotrophy

Answer 29

bacteria gain energy from light while using organic C substrates for catabolism

Question 30

enzymes

Answer 30

lowers activation energy

Question 31

tca/krebs

Answer 31

add acetyl-CoA.removes one C. (removal of co2)