Lecture 1 - Principles and Design of Metabolism

Question 1

What are the 2 major goals of metabolism?

Answer 1

1. Extract energy and reducing power from the environment

2. Synthesize building blocks needed to make more complex polymeric molecules

Question 2

_________ pathways are:

1. generally OXIDATIVE in nature;
2. involve breaking covalent bonds;
3. result in release of energy

Answer 2

Catabolic (degradative) pathways

Question 3

Glycolysis and fatty acid oxidation of examples of ______ pathways.

Answer 3

Catabolic pathways

Question 4

________ pathways are:

1. generally reductive in naturel
2. involve bond formation between smaller molecules to synthesize larger molecules;
3. consume energy

Answer 4

Anabolic (synthetic) pathways

Question 5

Glycogen synthesis and fatty acid synthesis are examples of _______ pathways.

Answer 5

Anabolic pathways

Question 6

The pathway of glycogen/glucose to form fatty acids/ketones/acetyl-CoA is called:

A. Lipogenesis
B. Ketogenesis
C. Gluconeogenesis
D. Synthesis of nonessential aa’s

Answer 6

A.

Question 7

The pathway of glycogen/glucose to form protein/amino acids is called:

A. Lipogenesis
B. Ketogenesis
C. Gluconeogenesis
D. Synthesis of nonessential aa’s

Answer 7

D

Question 8

The pathway of protein/amino acids to form fatty acids/ketones/acetyl-CoA is called:

A. Lipogenesis
B. Ketogenesis
C. Gluconeogenesis
D. Synthesis of nonessential aa’s

Answer 8

B

Question 9

The pathway of protein/amino acids to form glycogen/glucose is called:

A. Lipogenesis
B. Ketogenesis
C. Gluconeogenesis
D. Synthesis of nonessential aa’s

Answer 9

C

Question 10

_____ is a major carrier of electrons in oxidation reactions.

A. ATP
B. NAD+
C. NADPH
D. Coenzyme A

Answer 10

B (FAD is also a major carrier of electrons)

Question 11

______ is the universal carrier of acyl groups.

A. ATP
B. NAD+
C. NADPH
D. Coenzyme A

Answer 11

D

Question 12

_______ supplies the reducing power for biosynthetic reactions.

A. ATP
B. NAD+
C. NADPH
D. Coenzyme A

Answer 12

C

Question 13

Which type of skeletal muscle fibers contract rapidly, have limited duration and high capacity, and utilize glycogen and glucose breakdown with lactate formation?

Answer 13

White muscle fibers

Question 14

Which type of skeletal muscle fibers have limited aerobic oxidation due to low mitochondria content?

Answer 14

White muscle fibers

Question 15

Which type of muscle fibers are slower contracting and have a high mitochondria content?

Answer 15

Red muscle fibers

Question 16

Which type of muscle tissue has the highest density of mitochondria?

A. Skeletal
B. Heart
C. Liver
D. Brain and nerve

Answer 16

B

Question 17

The _______ plays a primary role in glucose homoestasis and stores glucose as glycogen.

Answer 17

liver

Question 18

What organ/system has high glycolytic and oxidative capacity, but cannot oxidize fatty acids?

Answer 18

brain/nerves

Question 19

The _______ carries out ammonia synthesis and gluconeogenesis using fatty acids, lactate, and ketones as fuels.

Answer 19

kidney

Question 20

The storage form of carbohydrates is:

A. Glycogen
B. Triglycerides
C. Glucose-6-P
D. Pyruvate
E. Lactate

Answer 20

A

Question 21

Which of the following is NOT a storage form of one of the fuel sources?

A. Glycogen
B. Triglycerides
C. Acetyl CoA
D. Protein

Answer 21

C (Acetyl-CoA is a tissue form.)

Question 22

Which of the following is NOT a circulating form of one of the fuel sources?

A. Amino acids
B. Triglycerides
C. Fatty acids
D. Lactate
E. Pyruvate
F. Ketones

Answer 22

E (Pyruvate is a tissue form.)

Question 23

Which is NOT one of the 4 key intermediates, or “branch points” in metabolism?

A. Glucose-6-P
B. Oxaloacetate
C. Pyruvate
D. Acetyl-CoA
E. Glutamate

Answer 23

B (Oxaloacetate is an intermediate in the conversion of pyruvate to G6P.)

Question 24

The 3 priorities in fuel metabolism after a meal are:

Answer 24

1. Meet the immediate energy needs
2. Replenish glycogen stores
3. Store all remaining calories as fat

Question 25

Stage ____ in extraction of energy is the conversion of building blocks to common intermediates.

A. Stage I
B. Stage II
C. Stage III
D. None of these

Answer 25

B

Question 26

Terminal oxidation of acetyl-CoA to CO2 and H2O, where most energy is extracted, is which stage in extraction of energy?

A. Stage I
B. Stage II
C. Stage III
D. None of these

Answer 26

C (Note - Stage III occurs in mitochondria.)

Question 27

Which is NOT a cytosolic pathway?

A. Pentose Phosphate Pathway
B. Fatty Acid Synthesis
C. Nucleotide Synthesis
D. Tricarboxylic Acid Cycle
E. Glycolysis

Answer 27

D (TCA Cycle is a mitochondrial pathway)

Question 28

Which is a pathway that uses both cytosolic and mitochondrial enzymes?

A. Oxidative phosphorylation
B. Ketogenesis and ketone oxidation
C. Gluconeogenesis
D. Glycolysis
E. Protein synthesis

Answer 28

C

Question 29

Which is a pathway that occurs in the smooth endoplasmic reticulum?

A. Triglyceride synthesis
B. Fatty acid synthesis
C. Nucleotide synthesis
D. Protein synthesis
E. Urea synthesis

Answer 29

A

Question 30

Where do ketogenesis and ketone oxidation occur?

A. Cytosolic Pathway
B. Mitochondrial Pathway
C. Both cytosolic and mitochondrial pathways
D. Smooth Endoplasmic Reticulum

Answer 30

B

Question 31

Where does cholesterol synthesis occur?

A. Cytosolic Pathway
B. Mitochondrial Pathway
C. Both cytosolic and mitochondrial pathways
D. Smooth Endoplasmic Reticulum

Answer 31

D