Deck 15: Metabolism: Basic Concepts and Design

Question 1

What type of organism obtains chemical energy from oxidation of complex carbon molecules?

A) chemotrophs
B) phototrophs
C) heterotrophs
D) autotrophs
E) None of the answers is correct.

Answer 1

A

Question 2

FAD is an electron carrier that is derived from the vitamin ________________.

Answer 2

riboflavin

Question 3

What vitamin is used to make the electron carrier NADH?

A) riboflavin
B) niacin
C) folate
D) biotin
E) thiamine

Answer 3

B

Question 4

Which of the following is the ultimate electron acceptor in aerobic organisms?

A) carbon dioxide
B) NAD⁺
C) FAD
D) oxygen
E) succinate

Question 5

That ATP has a high phosphoryl-transfer potential means that it is thermodynamically ____________ for ATP to transfer its terminal phosphoryl group to water.

Question 6

What type of pathway can be either anabolic or catabolic depending on the energy conditions of the cell?

A) amphipathic
B) amphiprotic
C) amphibolic
D) amphoteric
E) None of the answers is correct.

Question 7

Which of the following is the product from the complete oxidation of carbon-containing fuels under fully aerobic conditions?

A) oxygen
B) carbon monoxide
C) acetyl CoA
D) pyruvate
E) carbon dioxide

Question 8

A thermodynamically unfavorable reaction can be driven by a thermodynamically favorable reaction to which it is ________________.

Question 9

Which of the following serves as the "chemical currency" of metabolism?

A) NADH
B) acetyl CoA
C) NADPH
D) glucose
E) ATP

Question 10

In vertebrate muscle,_________________ serves as a reservoir of high-potential phosphoryl groups that can be readily transferred to ADP to regenerate ATP.

Question 11

An acetyl group can be attached to coenzyme A by a _______________ bond.

Question 12

_____________ is the first stage of human catabolism and involves the degradation of macromolecules in food into smaller units.

Question 13

What compound serves as an acyl carrier in metabolism?

A) FAD
B) biotin
C) thiamine pyrophosphate
D) coenzyme A
E) tetrahydrofolate

Question 14

What substance serves as the electron donor for most reductive biosynthetic pathways?

A) NADPH
B) NADH
C) FADH₂
D) FMNH₂
E) None of the answers is correct.

Question 15

_____________ reactions rearrange particular atoms within a molecule while conserving the empirical formula.

Question 16

ATP-generating (catabolic)pathways are inhibited by a ________ (high,low)energy charge.

Question 17

Which of the following is the term for small organic compounds that are components of coenzymes and are thus often required in the diets of higher organisms?

A) cofactor
B) metabolite
C) vitamin
D) metabolic intermediate
E) None of the answers is correct.

Question 18

In the second stage of catabolism,numerous small molecules are converted into _________________,a central molecule in metabolism.

Question 19

What type of organism uses energy from sunlight and converts it to chemical energy?

A) chemotrophs
B) phototrophs
C) heterotrophs
D) autotrophs
E) None of the answers is correct.

Question 20

In the cell,the hydrolysis of an ATP molecule in a coupled reaction changes the equilibrium ratio of _________ to _________ by a factor of 10⁸.

Question 21

What metabolic type of reaction involves the cleavage of bonds by the addition of water?

A) ligation
B) isomerization
C) lyase
D) oxidation-reduction
E) None of the answers is correct.

Question 22

Which of the following cellular processes require energy?

A) performance of mechanical work
B) facilitated diffusion
C) degradation of biomolecules
D) active transport
E) performance of mechanical work and active transport

Question 23

What general factors contribute to the high phosphoryl-group transfer of ATP?

Question 24

What metabolic type of reaction involves the addition of a functional group across a double bond or the removal of a functional group to form a double bond?

A) isomerization
B) group transfer
C) ligation requiring ATP
D) lyase
E) None of the answers is correct.

Question 25

Why is ATP frequently bound to magnesium or manganese ions?

Question 26

What is the standard-state free energy (?G°?)for the hydrolysis of ATP to ADP?

A) +45.6 kJ mol^-1
B) -45.6 kJ mol^-1
C) -30.5 kJ mol^-1
D) -015.6 kJ mol^-1
E) +30.5 kJ mol^-1

Question 27

Metabolic processes are regulated by

A) transcriptional regulation of the amount of enzyme.
B) allosteric control of enzyme activity.
C) accessibility of substrates by compartmentalization.
D) covalent modification of enzymes
E) All of the answers are correct.

Question 28

Which coenzymes contain adenosine phosphate units?

A) NADH
B) FADH2
C) coenzyme A
D) NADPH
E) All of the answers are correct.

Question 29

Explain how a metabolic pathway can contain an energetically unfavorable reaction yet still occur.

Question 30

Draw the structure of ATP and identify the phosphoanhydride bond(s).

Question 31

Which of the following molecules has a higher phosphoryl-transfer potential than ATP?

A) pyrophosphate
B) creatine phosphate
C) 2,3-bisphosphoglycerate
D) glucose-1-phosphate
E) None of the answers is correct.

Question 32

Which of the following is an example of an oxidation reaction?

A)
B)
C)
D) Ala-Ser + H₂O → Ala + Ser
E) None of the answers is correct.

Question 33

Which of the following is a 2-electron oxidizing agent used in catabolic pathways?

A) NAD⁺
B) FADH₂
C) Riboflavin
D) NADPH
E) None of the answers is correct.

Question 34

Which of the following is the electron donor used for reductive biosynthesis?

A) NADH
B) NADPH
C) FADH₂
D) CoA
E) ATP

Question 35

An example of an isomerization reaction would be

A) the conversion of succinate to fumarate using FAD.
B) the addition of carbon dioxide to pyruvate to form oxaloacetate.
C) the conversion of citrate to isocitrate.
D) the hydrolysis of a peptide bond.
E) None of the answers is correct.

Question 36

Metabolic pathways that require energy and are often biosynthetic processes are

A) anabolic.
B) catabolic.
C) allobolic.
D) All of the answers are correct
E) None of the answers is correct.

Question 37

The reduced form of flavin adenine dinucleotide is

A) FADH.
B) FAD.
C) FADH⁺⁺.
D) FADH₂.
E) None of the answers is correct.

Question 38

Which of the following is a mechanism by which enzyme catalytic activity is controlled?

A) allosteric control
B) feedback inhibition
C) covalent modification
D) allosteric control and covalent modification
E) All the answers are correct.

Question 39

Draw the resonance structures of orthophosphate,and explain why these structures are not significant in ATP.

Question 40

Reaction pathways that exclusively transform fuels into cellular energy are

A) anabolic.
B) catabolic.
C) allobolic.
D) amphibolic.
E) None of the answers is correct.

Question 41

If many compounds are common to both anabolic and catabolic paths,how can metabolism be controlled?

Question 42

List five activated carriers in metabolism,and give the vitamins that are the precursors of these carriers.

Question 43

How is metabolism controlled?

Question 44

What is the phosphorylation potential of a cell?

Question 45

Which of the metabolic chemical reactions is most commonly used to break down foodstuffs?

Question 46

How are metabolic processes unified? How can you use this to help learn and understand biochemistry?

Question 47

What is oxidative phosphorylation?

Question 48

What is an activated carrier? Provide two examples.

Question 49

How are thermodynamically unfavorable reactions driven?

Question 50

Compare ATP to acetyl CoA.