Unit 1 Review

Question 1

Glycolysis

Answer 1

Breaks 6C glucose into 2 3C pyruvate, forming 2 net ATP

Question 2

Citric Acid Cycle

Answer 2

Oxidizes acetyl CoA into 2 CO2, 3 NADH, 1 FADH2, 1 GTP

Question 3

Where does glycolysis occur?

Answer 3

The cytoplasm

Question 4

Where does the citric acid cycle occur?

Answer 4

The mitochondrial matrix

Question 5

PDH E1

Answer 5

Pyruvate Dehydrogenase (“Poor Drivers Don’t Take Defensive Driving” mnemonic)

Question 6

PDH E2

Answer 6

Dihydrolypoyl Transacetylase (“Poor Drivers Don’t Take Defensive Driving” mnemonic)

Question 7

PDH E3

Answer 7

Dihydrolipoyl Dehydrogenase (“Poor Drivers Don’t Take Defensive Driving” mnemonic)

Question 8

What does the PDH complex do?

Answer 8

Converts pyruvate to acetyl CoA

Question 9

What are the cofactors associated with PDH?

Answer 9

TPP, Lipoamide, CoA, FAD, NAD+

Question 10

Defining features of PDH steps

Answer 10

1) TPP E1 decarboxylates pyruvate, forming hydroxyethyl
2) Hydroxyethyl to dihydrolipoamide
3) Transesterification to Acetyl CoA
4) E3 takes protons from E2 (SH - DS)
5) E3 transfers protons to FAD, then NAD+

Question 11

What is the rate-limiting step of the citric acid cycle?

Answer 11

Enolate formation during citrate synthase rxn

Question 12

Citric Acid Cycle Mnemonic

Answer 12

Can I Keep Selling Seashells for Money, Officer?

Question 13

During which steps of the citric acid cycle are NADH formed?

Answer 13

Isocitrate dehydrogenase (+CO2), AKG dehydrogenase (+CO2), malate dehydrogenase

Question 14

During which step of the citric acid cycle is FADH2 formed?

Answer 14

Succinate Dehydrogenase

Question 15

During which step of the citric acid cycle is GTP formed?

Answer 15

Succinyl CoA synthetase

Question 16

Which enzyme in the citric acid cycle has a covalently bound FAD?

Answer 16

Succinate dehydrogenase (same one that produces FADH2)

Question 17

Which reaction in the citric acid cycle is endergonic?

Answer 17

Malate –> OAA (malate dehydr.)

Question 18

How many ATP generated per NADH?

Answer 18

2.5

Question 19

How many ATP generated per FADH2?

Answer 19

1.5

Question 20

Pyruvate dehydrogenase kinase _________ the PDH complex, insulin ________ activates.

Answer 20

PDK inhibits, insulin activates

Question 21

Allosteric inhibition of CAC

Answer 21

NADH and Acetyl CoA slow cycle

Question 22

3 Mechanisms of CAC Flux Control

Answer 22

Substrate Availability (e.g. OAA)
Product inhibition
Competitive feedback inhibition (e.g. NADH, acetyl CoA)

Question 23

Glyoxylate Cycle

Answer 23

Formation of OAA from 2 molecules acetyl CoA, skipping the CO2-producing step. Plants, bacteria, fungi (glyoxysome).

Question 24

What are the two new enzymes associated with the glyoxylate cycle?

Answer 24

Isocitrate lyase
Malate synthase

Question 25

What are the three substances that can freely diffuse through the IMM?

Answer 25

CO2, H2O, O2

Question 26

Malate-Aspartate Shuttle

Answer 26

Moves OAA into the matrix by temporarily converting it back to malate (AST Rxn). Heart, liver, kidneys.

Question 27

Glycerophosphate Shuttle

Answer 27

Lets NADH's electrons enter the ETS via FADH2, regenerating NAD+ for the CAC

Question 28

What molecule carries the electrons between CI, CII, and CIII?

Answer 28

CoQ/Ubiquinone

Question 29

What molecule carries the electrons between CIII and CIV?

Answer 29

Cytochrome C

Question 30

How many alpha-beta subunits in F1 of ATP synthase?

Answer 30

3

Question 31

Open conformation

Answer 31

Can't bind nucleotides

Question 32

Loose conformation

Answer 32

Can bind ADP and Pi

Question 33

Tight conformation

Answer 33

Can bind ATP

Question 34

What are the two gradients in the chemiosmotic model?

Answer 34

Electric and chemical gradients

Question 35

How many C subunits in human ATP synthase?

Answer 35

8 subunits

Question 36

What residue on ATP synthase picks up protons?

Answer 36

Glu or Asp

Question 37

P/O Ratio

Answer 37

Protons into IMS/4 protons per ATP

Question 38

2,4-DNP

Answer 38

Can cross membrane; dissipates gradient by grabbing protons then diffusing back into the matrix.

Question 39

Brown Adipose Tissue

Answer 39

UCP1 allows protons to reenter the matrix without going through ATP synthase

Question 40

Where do the light reactions take place?

Answer 40

Thylakoid Membrane

Question 41

Where is the high proton concentration generated during the light reactions?

Answer 41

Thylakoid lumen

Question 42

What does photosystem II do?

Answer 42

Oxidizes H2O, releases O2, and generates ATP

Question 43

What does photosystem I do?

Answer 43

Reduces NADP+

Question 44

Where does the Calvin Cycle occur?

Answer 44

Stroma

Question 45

What can be produced by G3P and DHAP isomerization?

Answer 45

Amylose, amylopectin, cellulose, sugars

Question 46

What happens if rubisco incorporates O2 instead of CO2?

Answer 46

Intermediate makes 1 G3P, 1 2-phosphoglycolate; glycolate to peroxisome for conversion to G3P (costs ATP, NADH)