Energy sources for muscle contraction

Question 1

4 Processes for deriving ATP in skeletal muscle

Answer 1

1) Aerobic production of ATP during exercises and normal conditions
2) Anaerobic production of ATP during intensive short-term work
3) Conversion of creatine phosphate to ATP
4) Conversion of ADP to one ATP and one AMP during heavy exercise

Question 2

Aerobic respiration - wher it occcurs, what it requires, and what it breaks down

Answer 2

Occurs in mitochondria
Requires O2
Breaks down glucose to produce ATP, CO2, and H2O

Can also process lipids or amino acids to make ATP

Slow-twitch fibers

Question 3

Anaerobic respiration

Answer 3

Does not require O2
Breaks down glucose to produce ATp and lactate
Fast-twitch fiberrs

Question 4

Which form of respiration is most efficient?

Answer 4

Aerobic respiration - produces 18x more ATP than anaerobic.

Takes several minutes

Question 5

Products of aerobic respiration

Answer 5

CO2
H2O
ATP

Question 6

Creatine phosphate

Answer 6

Stored in muscles
Can be rapidly used to maintain adequate ATP in contracting muscle fibers
Is used up very quickly - 8-10 seconds to sustain maximum muscle contraction

Question 7

Fatigue

Answer 7

Temporary state of reduced work capacity

Question 8

What causes fatigue? (3)

Answer 8

1. Acidosis and ATP depletion (either due to ATP consumption or decrease in ATP production
   2) Oxidative stress
   3) Local inflammatory reactions

Question 9

Acidosis and ATP depletion

Answer 9

Breakdown fo glucose > lactate causes lowered pH > decreases effectiveness of Ca2+ on actin nad less Ca2+ release from arcoplasmic reticulum

Question 10

Interleukin-6

Answer 10

an immune system response from ROS which mediates inflammation, causing soreness

Question 11

Physiological contracture

Answer 11

extreme muscle fatigue causes a complete inability for muscles to relax or contract.

Too little ATP to bind to myosin filaments

Question 12

Psychological fatigue

Answer 12

The central nervous system makes individual perceive that continued muscle contraction is impossible

Question 13

Rigor mortis

Answer 13

rigid muscles developing several hours after death.

ATP production stops > Ca2+ levels increase in sarcoplasm and form cross bridges, but without ATP to bind to myosin, so they can’t contract.

Question 14

Muscle soreness

Answer 14

inflammatory chemicals in muscle fibers > enzymes normally found in muscle fibers are in extracellular fluid due to a rupture or increased permeability

Question 15

Oxygen deficit

Answer 15

insufficient oxygen consumption relative to increased activity at the onset of the exercise

Question 16

Sources of ATP in Skeletal muscle

Answer 16

Creatine phosphate (10 s)
Anaerobic respiration (glucose) (3 min)
Aerobic respiration (glucose, fatty acids, amino acids (Hours

Question 17

recovery oxygen consumption

Answer 17

Elevated oxygen consumption after exercises // a portion of the recovery oxygen “repays” the oxygen deficit from teh start of the exercise.

Most of the recovery oxygen support metabolic processes to restore homeostasis