Bioenergetics of Muscle Contraction

Question 1

insufficient ATP sources can present as ________ or _______

Answer 1

• muscle weakness

- exaggerated fatigability

Question 2

exercise and disease states can change the _____ of muscle types

Answer 2

proportion

Question 3

4 main sources of energy for skeletal muscles

Answer 3

• glycogen
• carbohydrates
• phosphocreatine
• fats

Question 4

anaerobic metabolism methods

Answer 4

• phosphocreatine

- glycolysis

Question 5

aerobic metabolism process

Answer 5

Krebs cycle

Question 6

___________ breaks phosphocreatine into creatine and ATP

Answer 6

creatine kinase

Question 7

↑ ADP _______ creatine kinase

↑ ATP _______ creatine kinase

Answer 7

• activates

- inhibits

Question 8

4 effects of creatine supplementation

Answer 8

• ↑ muscle mass
• ↓ body fat
• ↑ short-term strength
• some evidence of protective effect in muscle wasting diseases

Question 9

what are the potential risks of creatine supplementation?

Answer 9

increased heat production and changes in renal function

Question 10

the energy investment phase of glycolysis starts with ________ and ends with _____

Answer 10

• glucose

- glyceraldehyde 3-phosphate (x2)

Question 11

the energy release phase of glycolysis starts with __________ and ends with __________

Answer 11

• glyceraldehyde 3-phosphate

- pyruvate

Question 12

What are the net products of glycolysis?

Answer 12

2 ATP
2 NADH
2 pyruvate

Question 13

_____________ is the enzyme that catalyzes the reaction to produce pyruvate

Answer 13

phosphofructokinase (PFK)

Question 14

__________: an inherited autosomal recessive disorder caused by PFK deficiency

Answer 14

Tarui’s disease

Question 15

symptoms of Tarui’s disease

Answer 15

• excessive glycogen storage
• discolored/darker urine
• muscle weakness
• cramps
• anemia
• exercise intolerance

Question 16

what is the result of Tarui’s disease?

Answer 16

lack of PFK prevents the metabolism of glucose into energy and destroys red blood cells

Question 17

3 concentration conditions that will inactivate PFK

Answer 17

• ↑ ATP
• ↑ phosphocreatine
• ↓ pH

Question 18

3 concentration conditions that will activate PFK

Answer 18

• ↑ ADP
• ↑ P ion
• ↑ pH

Question 19

an increase in glycogenolysis is caused by __

Answer 19

↑ sarcoplasmic Ca++ indirectly by circulating catecholamines

Question 20

a decrease in glycogenolysis is caused by _______

Answer 20

decreasing sarcoplasmic Ca++

Question 21

What disease is described?

• exercise intolerance
• cramps
• muscle pain and weakness shortly after beginning exercise
• “second wind” after resting

Answer 21

phosphorylase deficiency (McArdles disease in humans)

Question 22

as the duration of exercise increases and carbohydrate stores decline, utilization of _________ increases

Answer 22

fats

Question 23

what is the total ATP aerobic production?

Answer 23

38 ATP

Question 24

what is the key enzyme in the Kreb’s cycle?

Answer 24

isocitrate dehydrogenase

Question 25

3 conditions that increase the Kreb’s cycle

Answer 25

• ↑ ADP
• ↑ P ion
• ↑ mitochondrial Ca++

Question 26

↑ ATP has what effect on the Kreb’s cycle?

Answer 26

inhibitory

Question 27

circulating catecholamines trigger ________ release

Answer 27

glucagon

Question 28

circulating __________ will trigger glucagon release

Answer 28

catecholamines

Question 29

what is the purpose of GLUT-4?

Answer 29

insulin-independent glucose transport

Question 30

there is an increase in type ______ muscle fibers in diabetes

Answer 30

II (fast twitch)