Lecture 15

Question 1

True or false.

Catabolism is the breakdown of material and anabolism is the synthesis of complex organic compounds

Answer 1

True

Question 2

True or false

Anabolism needs a net energy input whereas catabolism creates a net energy output

Answer 2

true

Question 3

What is the difference between heterotrophs and autotrophs?

Answer 3

Autographs are able to make material simply from CO2 whereas heterotrophs need to get their energy and metabolites from other organic compounds

Question 4

What is the general net output of glycolysis?

Answer 4

2 ATP 2 NADH 2H+ 2H20

Question 5

true or false

glycolysis can continue without oxygen presence

Answer 5

true

Question 6

true or false

glycerol and amino acids can enter the gluconeogenic pathway at glyceraldehyde-3-phosphate and pyruvate respectively

Answer 6

true

Question 7

True or false

Gluconeogenesis can aid in the synthesis of glycogen

Answer 7

true

Question 8

What is a futile cycle?

Answer 8

when cycles are unchecked and ATP will be used up with no progress in either direction of a cycle

Question 9

What are the main activated carriers in metabolism?

Answer 9

ATP = activated carrier of phosphoryl groups

NADP and NADPH = carrier of electrons

FADH2 = carrier of electrons

Acetyl CoA = carrier of two-carbons molecules

Question 10

The basic structure of NAD+ is:
A) base-sugar-sugar-phosphate-sugar-base
B) base-sugar-phosphate-phosphate-sugar-base
C) sugar-base-phosphate-phosphate-base-sugar
D) none of the above are the basic structure of NAD+

Answer 10

B

Question 11

true or false

each electron is associated with an H+ molecule

Answer 11

true

Question 12

True or false

the vitamin niacin is the derivative of NAD+

Answer 12

true

Question 13

Based on your knowledge of NAD+, which of the following statements is true?
A) it contains a 3 phosphate group total in its compound
B) Its reduced form contains an additional H on its compound and there is also an extra H+ in solution
c) NAD+ is an inorganic cofactor
D) it is derived from a non-essential amino acid

Answer 13

B

Question 14

true or false.

NAD+ contains a purine base and its reactive group is the nicotinamide group

Answer 14

true

Question 15

true or false.

Reduction of NAD+ results in a more acidic solution

Answer 15

true

Question 16

true or false NAD+ is a reductant and is oxidized

Answer 16

false, reverse

Question 17

When comparing NAD+/NADH and NADP+/NADPH, which of following statements is NOT true?
A) NAD+/NADH is involved in catabolic reactions
B) NADPH/NADP+ reactions typically work with reducatases whereas NAD+/NADH tend to work with dehydrogenases
C) NADP+ can be transformed to NAD+ by a mitchonchondrial linked transhydrogenase
D) NADPH/NADP+ tend to work in oxidative pathways whereas NAD+/NADH tend to work in reductive pathways

Answer 17

D

Question 18

true or false

NAD+ kinase can transform NAD+ to NADP+

Answer 18

true

Question 19

true or false

reductases involve the reduction of substrates whereas dehydrogenases involve the oxidation of substrates

Answer 19

true

Question 20

What are the change in free energy equations relating enthalpy and entropy as well as concentration?

Answer 20

G= H -TS
G= G0' + RTln(CD/AB)

Question 21

true or false

energy needed to drive biosynthetic reactions is driven by the reduction of organic substrates

Answer 21

false. oxidation of organic substrates is a function of catabolic reactions, which produce energy. Reduction is the role of anabolic reactions and involves net input of energy

Question 22

Which of the following compounds is NOT able to couple to ATP synthesis?
A) PEP
B) BPG
C) Glucose-6-phosphate
D) Creatine phosphate

Answer 22

C

Question 23

True or false.

The most favorable phosphorylated compound of main donor groups is phosphoenol pyruvate

Answer 23

true

Question 24

True or false

One would expect creatine phosphate levels to be high when ATP levels are low

Answer 24

false. One would expect creatine levels to be high since this is a product of ATP synthesis

Question 25

``` Which of the following are NOT quick regulators of metabolic activity? A) controlling enzyme amount B) substrate level control C) allosteric control D) reversible covalent modifications ```

Answer 25

A

Question 26

true or false | glycolysis is a universal process in most living cells

Answer 26

true

Question 27

What are the two main stages of Glycolysis and their function?

Answer 27

Energy investment and Energy generation energy investment is to trap and prime the glucose and energy generation is to oxidized products of stage 1 to pyruvate and to harvest ATP

Question 28

True or false | Glycolysis occurs in the mitochondrial matrix

Answer 28

false. cytosol

Question 29

What are the 3 fates of pyruvate after glycolysis?

Answer 29

enter TCA cycle, make lactate, or make ethanol under anaerobic fermentation

Question 30

true or false | Fermentation generates energy but does not change the overall oxidation state of the carbon substrate

Answer 30

true

Question 31

True or false | Anaerobic respiration occurs in the cytosol

Answer 31

true

Question 32

True or false | Lactate dehydrogenase is responsible for the regeneration of NAD+

Answer 32

true

Question 33

True or false | One would expect the the activity of lactate fermentation to increase as pH decreases

Answer 33

true

Question 34

True or false | lactate and pyruvate are both 3 carbon molecules

Answer 34

True

Question 35

True or false. | One would expect an increase in pH to increase the rate of NADH product

Answer 35

True

Question 36

True or false | the delta g of lactate production is -25.1 kj/mol

Answer 36

true

Question 37

What is the net product of Lactate fermentation per glucose?

Answer 37

2 Lactate 2 ATP and 2 H20

Question 38

What is hormonal regulation?

Answer 38

- - specific cells, target cells | - - respond to hormones if they have a specific receptor protein on their surface

Question 39

What is an overview of glycolysis?

Answer 39

-- 6 carbon sugar is split into 2 3-carbon molecules -- ATP is formed from energy released during this process -- can proceed under aerobic or anaerobic conditions -- regulation is well understood -- universal process in most living cells and plays a central metabolic role by generating energy and intermediates for other pathways

Question 40

What is the difference between energy investment and energy generation?

Answer 40

1. Glucose --> glyceraldehyde 3-phosphate (GAP) - -------> trapping and priming - -------> attaching phosphate to low energy bond to make something that will release a lot energy later 2. Oxidation to GAP to pyruvate harvesting ATP

Question 41

Per glucose how much ATP is consumed, how much is produced and how much NADH is produced?

Answer 41

- - 2 ATP consumed and 4 ATP and 2 NADH are produced | - ----> net production 2 ATP and 2 NADH

Question 42

where does glycolysis take place?

Answer 42

-- located in cytosol

Question 43

What are the three different fates for pyruvate post-Glycolysis?

Answer 43

-- Acetaldehyde --> Ethanol (anaerobic alcoholic fermentation) -- Lactate (anaerobic homolactic fermentation) -- Acetyl CoA --> further oxidation (aerobic)

Question 44

T or F, fermentation generates energy, but no overall change in oxidation state of the carbon substrate

Answer 44

True

Question 45

T or F, since NAD+ is needed for glycolysis (ATP production) is must be recycled back after glucose is broken down

Answer 45

True; NADH is re-oxidized by reducing pyruvate to lactate

Question 46

What is the benefit of recycling NAD+ w/ NADH?

Answer 46

-- allows glycolysis to continue even in absence of oxygen

Question 47

T or F, some reactions are so exergonic they're irreversible

Answer 47

True

Question 48

What is the fermentation of pyruvate to lactate?

Answer 48

-- reaction occurs in microorganisms and in our tissues whenever pyruvate is produced faster than it can be oxidized in the Citric Acid Cycle, conditions of low oxygen availability (e.g. strenuous exercise)