Ch 8: Glucose Metabolism

Question 1

Metabolism

Answer 1

the sum of all chemical reactions in an organism

Question 2

catabolism

Answer 2

the breakdown of input molecules converted to products

energy is usually produced and is stored in high energy aka ATP and NADH

Question 3

anabolism

Answer 3

synthesis of complex molecules

energy is required

Question 4

Gibbs Free energy

Answer 4

(G)

energy defined for constant temp and pressure

Question 5

∆G

Answer 5

delta g
difference in energy btw reactants and products

∆G=Gproducts-Greactants

Question 6

∆G^0

Answer 6

if reactants and products are at equilbrium, then ∆G^0 is used

Question 7

neg value of ∆G

Answer 7

means process is favorable aka free energy is released, downhill, exergonic, spontaneous

Question 8

pos value of ∆G

Answer 8

means process is unfavorable aka free energy is consumed, not spontaneous, unfavorable, uphill, and endergonic

Question 9

units of energy

Answer 9

1 kcal/mol=4.17 kJoule/mol

Question 10

ATP

Answer 10

non redox high energy compound

ATP+H2O–>ADP+Pi

ADP +Pi=more favorable and more stable bc of lower energy

∆G=-7.3 kcal/mol

Question 11

NADH

Answer 11

redox high energy compound

∆G= -52.4

Question 12

redox reactions

Answer 12

one substance transferring electrons to another substance

Question 13

reduction

Answer 13

gain of electrons

Question 14

oxidation

Answer 14

loss of electrons

Question 15

reducing agent

Answer 15

gives up an electron

Question 16

oxidizing agent

Answer 16

takes on electrons

Question 17

redox rules (oxidation)

Answer 17

• Oxidation
o Product has 2 fewer H atoms than the substrate or product has 1 more oxygen atom than substrate
o Substrate is the more reduced form and product is the more oxidized form; product has two fewer electrons than substrate
o The two electrons given up by substrate are usually transferred to NAD+ to give NADH
• Ex: [NAD^+ +H3C-CH2OH+H2O→H3C-COH + NADH + H+]

Question 18

Redox rules (reduction)

Answer 18

o Product has 2 more H atoms than the reactant or product has 1 fewer oxygen atom than reactant
o Substrate is the more oxidized form and product is the more reduced form; product has two more electrons than substrate
o The two electrons accepted by substrate have usually come from NADH to give NAD+

Question 19

Cellular respiration equation

Answer 19

C6H12O6+6O2–>6CO2+6H2O+ free energy (-686 kcal/mol)

favorable

Question 20

glycolysis

Answer 20

occurs in cytoplasm

generates no CO2

10 enzymatic steps

outcome: 2 pyruvate, 2 ATP, 2 NADH

Question 21

Steps 1-3 of glycolysis

Answer 21

1) Phosphate (from ATP) converts to C6-OH of glucose
2) Carbonyl C1=O of glucose 6 phosphate moves to C2=O fructose 6phosphate
3) Phosphate (from ATP) to C1-OH of fructose-6 phosphate

Question 22

Steps 4 and 5 of glycolysis

Answer 22

Break C3-C4 bond to get two 3 carbon phosphosugars

interconvert the two 3 carbon phospho-sugars

Question 23

steps 6&7 of glycolysis

Answer 23

generate 2xNADH

generate 2x ATP

Question 24

Steps 8&9

Answer 24

Make 2xPEP

Question 25

Step 10

Answer 25

phosphates from 2xPEP transferred to to 2xADP to make ATP

Question 26

pyruvate dehydrogenase

Answer 26

pyruvate is converted to acetyl CoA and CO2

includes the breaking of a C-C bond

2 acetyl CoA, 2 NADH, 2 CO2

Question 27

citric acid cycle

Answer 27

transforms acetyl CoA into 2 CO2 molecules

Four redox reactions
3 generate NADH and one generates FADH2

4 CO2, 2 ATP, 6 NADH, 2 FADH2

one C-C bond is formed and then 2 C-C bonds are broken

Question 28

ETC

Answer 28

in eukaryotes, ETC is located in the inner mitochondrial membrane

1) NADH transfers electrons to Complex I
2) electrons are then transferred to ubiquinone
3) ComplexIII
4) cytochrome C
5) Complex iV
6) oxygen

FADH2 transfers its two electrons to Complex II, which transfers those electrons to ubiquinone

Question 29

proton gradient

Answer 29

Complexes I, III, IV, pump protons (H+) from inside the mitochondria across the inner mitochondrial membrane to the intermembrane space

2) when the proton is deposited into the inter-membrane space, it leaves a behind a hydroxide ion inside the mitochondria
3) leads to an excess of H+ protons outside the mitochondria
4) creates a potential energy gradient across the membrane

Question 30

ATP Synthesis

Answer 30

1) proton gradient provides the free energy to synthesize ATP

• Excess protons on the outside of the mitochondria are allowed to leak back from outside-to-inside through a special channel in a protein called “ATP synthase”
• Protons travel through a channel in the F0 unit and as they come through, they cause the synthesis of ATP in the F1 unit (inside of the mitochondria)
o ADP has 3 neg charges, Pi has 2 neg charges