Metabolism

Question 1

which complex contains cytochromes b and c1 and an Fe-S center:
complex I, II, III, IV?

Answer 1

complex III

Question 2

electrons from NADH are transferred to the __

Answer 2

FMN prosthetic group of NADH-Q: COMPLEX I

Question 3

succinate dehydrogenase (the enzyme found in TCA) is in complex

Answer 3

COMPLEXII

Question 4

the mobile carriers of electrons are

Answer 4

cytochrome c and Q

Question 5

cytochrome c oxidase is

Answer 5

Complex IV

Question 6

cytochromes a and a3 are in

Answer 6

complex IV

Question 7

how many molecules of ATP per NADH oxidized

Answer 7

2.5

Question 8

how many molecules of ATP per FADH2 oxidized

Answer 8

1.5

Question 9

glucokinase is in the

Answer 9

liver!

Question 10

difference bw glucokinase and hexokinase:

1. which one has higher affinity (lower Km)
2. which one can only catalyze glucose

Answer 10

1. glucokinase has lower affinity
2. glucokinase only glucose
   While other hexokinases are capable of phosphorylating several hexoses, glucokinase acts with a 50-fold lower substrate affinity and its only hexose substrate is glucose

Question 11

cycle where glucose and lactate shuttle bw muscle and liver

Answer 11

cori cycle aka lactic acid cycle

Question 12

the cori cycle functions more efficiently when muscle activity has

Answer 12

ceased bc oxygen debt can be made up so that the citric acid cycle and electron transport chain also work

Question 13

2 places in body lactic acid produced

Answer 13

RBC and active muscle

Question 14

pyruvate is converted to acetyl coA by

Answer 14

pyruvate dehydrogenase = enzyme

NAD+, CoA, and pyruvate ==> CO2 + Acetyl-CoA + NADH

Question 15

pyruvate is converted to lactic acid by

Answer 15

lactate dehydrogenase = enzyme

pyruvate + NADH ==> lactate + NAD+

Question 16

the glycolytic pathway is:

a. aerobic
b. anaerobic
c. facultative

Answer 16

it is called ANAEROBIC bc it does not need oxygen

Question 17

what happens to the carbons and oxygens of glucose?

Answer 17

released as waste! one carbon lost from pyruvate ==> Acetyl CoA ==> TCA lose the other two

Question 18

is TCA

a. aerobic
b. anaerobic
c. facultative

Answer 18

a. aerobic

Question 19

glycolysis is _ and TCA is __

a. aerobic
b. anaerobic
c. facultative

Answer 19

glycolysis anaerobic

TCA aerobic

Question 20

the most common pathway of glycolysis is

Answer 20

Embden-Meyerhof pathway

Question 21

Embden-Meyerhof pathway is a specific glycolytic pathway by which

Answer 21

glucose converted to pyruvate

Question 22

oral bacteria use which pathway

Answer 22

Embden-Meyerhof pathway = anaerobic and facultative bacteria

Question 23

Embden-Meyerhof pathway will take pyruvate and

Answer 23

make lactic acid and 2 ATP per molecule of glucose metabolized

Question 24

the Entner Doudoroff pathway is an alternative to glycolysis used by many _ bacteria

Answer 24

obligate aerobic bacteria.

Question 25

1. the Entner Doudoroff pathway results in the net production of _ ATP 2. Embden-Meyerhof pathway results in the net production of _ ATP

Answer 25

1. one ATP by substrate level phosphorylation | 2. two ATP

Question 26

the Entner Doudoroff pathway ends with production of

Answer 26

pyruvate and glyceraldehyde 3 phosphate (which is converted by enzymes outside the pathway to pyruvate).

Question 27

the Entner Doudoroff pathway bacteria lack which enzymes of the Embden-Meyerhof pathway?

Answer 27

either 6-PFK or aldolase

Question 28

the _ pathway oxidized hexose and glucose 6 phosphate makes 5C sugars. it generates reducing equivalents ___

Answer 28

pentose phosphate pathway | NADPH

Question 29

NADPH is used in ___ reactions

Answer 29

reductive biosynthesis pathways (FA/steroid synthesis) remember oxidative pathways are catabolic ie. just remember glucose

Question 30

does the pentose phosphate pathway | require ATP for phosphorylation

Answer 30

no. no ATP is consumed or produced directly in the cylce

Question 31

pentose phosphate pathway | consists of 2 __ oxidative reactions followed by a series of reversible sugar phosphate interconversions

Answer 31

irreversible

Question 32

pentose phosphate pathway | occurs where in the cell

Answer 32

cytosol

Question 33

pentose phosphate pathway | produces ribose 5 phosphate which is required for

Answer 33

synthesis of nucleotides

Question 34

the __branch of the pentose phosphate pathway | synthesizes NADPH

Answer 34

oxidative

Question 35

the rate limiting step in pentose phosphate pathway enzyme

Answer 35

G6P DH

Question 36

the _ branch links ribulose 5 P (the product of the oxidative rxns) to glycolytic and gluconeogenic pathways

Answer 36

non oxidative

Question 37

most important enzymes in the reversible reactions of the non oxidative PPP are

Answer 37

tranketolase and transaldolase

Question 38

PPP activity is _ in muscle and brain

Answer 38

minimal.

Question 39

PPP important in what organs

Answer 39

liver and mammary glands adrenal cortex

Question 40

PPP important in cells exposed to high

Answer 40

oxygen partial pressure

Question 41

___ pathway important in cornea of eye

Answer 41

cornea of eye = 60% of total glucose consumption via PPP

Question 42

the _ portion of PPP is not reversible

Answer 42

oxidative | makes NADPH

Question 43

the __ portion of PPP generates the sugars so they can re enter glycolysis

Answer 43

nonoxidative

Question 44

__ is the first phase of respiratory metabolism of glucose and _ is the 2nd, and _ is the 3rd

Answer 44

glycolysis tca e transport chain

Question 45

photophosphorylatin occurs as a result of

Answer 45

photosynthesis (which also involves the electron transport chain)

Question 46

oxygen uptake which is dependent on the presence of ADP phosphate and an electron donor is called

Answer 46

coupled respiration

Question 47

THEORETICALLY most human cells: one glucose molecule produces enough chemical energy to synthesize: 32-34 ATP 36-38 ATP

Answer 47

36-38

Question 48

which cells may synthesize 38 electrons?

Answer 48

heart and liver cells that shuttle electrons more efficiently

Question 49

a net profit of _ ATP is produced by substrate level phosphorylation during glycolysis and TCA

Answer 49

4 ATP (2 glycolysis + 2 TCA)

Question 50

___ ATP form oxidative phosphorylation

Answer 50

32-34ATP during e- transport

Question 51

glucose is completely oxidized to

Answer 51

CO2 and water (not oxygen!!!! oxygen is the final electron acceptor and turns into water)

Question 52

THEORETICALLY glucose oxidation to CO2 and H20 makes _ ATP | in reality it is

Answer 52

theoretically: 36-38 (counting NADH as 3ATP and FADH2 as 2ATP - theoretical) in realtiy: 30-32ATP (really NADH is 2.5 and FADH2 is 1.5)

Question 53

T/F gluconeogenesis is the reverse of glycolysis

Answer 53

false

Question 54

gluconeogenesis produces glucose from (3)

Answer 54

amino acids lactate glycerol

Question 55

gluconeogenesis uses the __ reactions of glycolysis and bypasses the __ ones

Answer 55

uses the reversible steps and bypasses the irreversible steps

Question 56

__ is the only source of glucose during long term fasting

Answer 56

gluconeogenesis

Question 57

only the _ can do GNG

Answer 57

liver and kidneys

Question 58

how many steps in GNG

Answer 58

11

Question 59

GNG begins in the _ with the formation of _. enzyme? energy?

Answer 59

mitochondria forms OAA pyruvate + CO2 +ATP ==> OAA pyruvate carboxylase

Question 60

OAA is then reduced to __ using __ in order to be transported out of mitochondria in GNG

Answer 60

malate | NADH

Question 61

Name the enzymes in GNG that are unique

Answer 61

pyruvate carboxylase (pyruvate ->OAA) PEP carboxykinase (OAA --> PEP) F1,6 Bisphosphatase (F1,6BP -->F1,6) glucose 6 phosphatase: in ER, forms glucose

Question 62

1. lactate dehydrogenase | 2. pyruvate dehydrogenase

Answer 62

1. make lactic acid | 2. make acetylCoA