T01 - Introduction to Metabolism

Question 1

Metabolism consists of what two primary energy processes?

Answer 1

catabolism; anabolism

Question 2

Catabolism is primary responsible for

Answer 2

energy production

Question 3

Anabolism is primarily responsible for

Answer 3

the synthesis of macromolecules

Question 4

Draw a diagram that illustrates the consumption and regeneration of electron carriers in catabolism and anabolism.

Answer 4

Question 5

What are the two factors that determine energy need requirements?

Answer 5

basal energy expenditure (BEE)

body mass index (BMI)

Question 6

What is the First Law of Thermodynamics?

Answer 6

energy can neither be created nor destroyed, but can be converted from one form to another

Question 7

Draw an energy diagram that shows the stepwise oxidation of sugar in cells.

Answer 7

Question 8

Draw an energy diagram that shows the direct burning of sugar in cells.

Answer 8

Question 9

Write out the chemical reaction showing hydrolysis of ATP into ADP and P_i. What is the ΔG°’ of this reaction?

Answer 9

ATP + H₂O → ADP + P_i

ΔG°’ = -7.3 kcal/mol

Question 10

Write out the chemical reaction showing hydrolysis of ATP into AMP and PPi. What is the ΔG°’ of this reaction?

Answer 10

ATP + H₂O → AMP + PP_i

ΔG°’ = -10.9 kcal/mol

Question 11

Describe the energy “composition” of a typical 70 kg man.

Answer 11

1,600 kcal in glycogen

24,000 kcal in mobilizable protein

135,000 kcal in fat

Question 12

What molecule is, by far, the largest fuel source in mammals?

Answer 12

fat

Question 13

What is the metabolic energy equivalent for carbohydrates?

Answer 13

4 kcal/g

Question 14

What is the metabolic energy equivalent for protein?

Answer 14

4 kcal/g

Question 15

What is the metabolic energy equivalent for fat?

Answer 15

9 kcal/g

Question 16

What molecule serves as the primary carbohydrate/metabolic fuel in mammals?

Answer 16

glucose

Question 17

Outline the path of glucose as a metabolic fuel. (7)

Answer 17

glucose → [glycolysis] → pyruvate → acetyl-CoA → [TCA coupled to reduction of NAD⁺ and FAD to NADH and FADH₂] → [electron transport chain] → [ox phos] → ~36 ATP

Question 18

Give two major (alternative) energy sources in mammal (other than glucose).

Answer 18

fatty acids

amino acids

Question 19

Outline the pathway of fatty acids as a metabolic fuel. (2)

Answer 19

palmitate → [complete oxidation] → ~129 ATP

Question 20

Outline the two pathways of amino acids as a metabolic fuel.

Answer 20

AA → [transaminase] → keto-acid → [feed into TCA or glycolysis]

AA → [feed into gluconeogenesis]

Question 21

What two hormones are the primary regulators of metabolism?

Answer 21

insulin and glucagon

Question 22

Insulin promotes

Answer 22

storage of simple monomeric fuels in polymeric form

Question 23

Glucagon promotes

Answer 23

oxidation of polymeric storage depots to yield monomeric units for fuel

Question 24

Describe the relative activities of insulin and glucagon in anabolism.

Answer 24

insulin activity increased

glucagon activity decreased

Question 25

Describe the relative activities of insulin and glucagon in catabolism.

Answer 25

insulin activity _decreased_ glucagon activity _increased_

Question 26

What is fuel source in anabolism?

Answer 26

diet

Question 27

What is fuel source in catabolism?

Answer 27

storage depots

Question 28

Basal energy expenditure results from what two actions?

Answer 28

heat production keeping the brain alive

Question 29

Write out the equation to calculate BMI.

Answer 29

Question 30

What are the BMI intervals and their associated weight statuses?

Answer 30

below 18.5 = underweight 18. 5 - 24.9 = normal 25. 0 - 29.9 = overweight \>30.0 = obese

Question 31

Rank carbohydrates, amino acids, and fats in terms of ease of metabolism.

Answer 31

carbohydrates \> amino acids \> fats

Question 32

What are the symptoms of metabolic syndrome? (4)

Answer 32

increased blood pressure high blood glucose body fat around the wait abnormal cholesterol or triglyceride levels

Question 33

What are the risk factors for metabolic syndrome? (3)

Answer 33

age race obesity

Question 34

What is the pathology of metabolic syndrome?

Answer 34

diabetes cardiovascular disease

Question 35

Rank methane, methanol, formaldehyde, formic acid, and carbon dioxide in terms of ΔG°, going from most negative to least negative.

Answer 35

more C-H bonds in small molecules = more energy oxidation of methane is most favorable (most negative ΔG° value)

Question 36

What are the high-energy bonds within ATP?

Answer 36

the bond between alpha and beta, and the bond between beta and gamma the bond between the ribose and alpha phosphate is _low energy_

Question 37

The conversion of ATP to ADP is associated with what processes? (4)

Answer 37

motion active transport biosyntheses signal amplification

Question 38

The conversion of ADP to ATP is associated with what processes?

Answer 38

oxidation of fuel molecules photosynthesis

Question 39

Describe how ATP is used to drive unfavorable reactions, using glutamic acid as an example.

Answer 39

phosphate transferred from ATP to glutamic acid to form _high-energy intermediate_ phosphate (P_i) released and NH3 added to form glutamine therefore, products of ATP hydrolysis are ADP and P_i

Question 40

Draw a diagram that shows the relationship between NADP+, NADPH, catabolism, and anabolism.

Answer 40

Question 41

Glycolysis occurs in what cellular structure?

Answer 41

cytosol

Question 42

Insulin is produced by

Answer 42

the beta cells of pancreatic islets

Question 43

Glucagon is synthesized by

Answer 43

alpha cells of the pancreas