Muscles Pt. 2 Flashcards
What are the 3 sources of energy in muscle?
- Carbohydrates.
- Free Fatty Acids (FFA).
- Phosphocreatine.
What source of energy is the most readily available?
Phosphocreatine (PCr).
What is phosphocreatine?
A high energy phosphate group similar to ATP.
How do PCr and ADP interact?
In the presence of creatine kinase, PCr donates a phosphate group to the ADP to form ATP.
*Reversible reaction.
What is the second most utilized/available method for ATP production?
Glycolysis.
What are the two types of glycolysis?
- Anaerobic.
- Aerobic.
What is produced during anaerobic glycolysis?
Lactate/Lactic acid.
How many ATP are produced when glucose is converted to lactate?
2 ATP molecules.
How many ATP are produced from glucose and 2 ATP being converted into lactic acid?
4 ATP total, 2 per lactic acid.
*If converted to glycogen, net of 3 ATP.
What is produced during aerobic glycolysis?
Pyruvate production.
What process does glucose undergo to produce pyruvate (general)?
Catabolism.
What component of the citric acid cycle is glucose converted into?
Acetyl-CoA.
Where is glucose stored as glycogen?
- Liver.
- Muscle.
What is the equation for aerobic glycolysis?
C6H12O6 +6O2 —> 6 CO2 + 6 H2O + 38 ATP.
What duration of exercise is fueled by stored ATP and creatine phosphate?
10-15 seconds.
What duration of exercise is fueled by the anaerobic metabolism of glucose?
15 seconds to 2-3 minutes.
What duration of exercise is fueled by aerobic metabolism of glucose, fatty acids, and some proteins?
2-3 minutes and beyond.
*Anaerobic metabolism will contribute for higher intensity spans.
What is a triglyceride composed of?
A glycerol and 3 attached free fatty acids.
Where are triglycerides found?
Adipose and muscle cells.
What is the equation for B-oxidation?
C16H32O2 + 23O2 —> 16 CO2 + 16 H2O + 129 ATP.
When are triglycerides primarily used?
Endurance exercise.
What are 2 other energy sources the body may utilize?
- Volatile Fatty Acids (Ruminant and Non-Ruminant herbivores only).
- Protein.
What are the 3 Volatile Fatty Acids (VFAs)?
- Acetate/Acetic acid.
- Butyrate/Butyric acid.
- Propionate/Propionic acid.
*Enter the citric acid cycle at a different point than pyruvate.
Under what conditions is protein utilized for energy?
- Prolonged exercise.
- Starvation/malnutrition.
How is protein utilized for energy?
AA are transported to the liver to be converted into glucose or various oxidative metabolism intermediates.
What % of energy in food is actually received for activity?
20-30%.
How is a slow rate of contraction described?
- High heat.
- Low efficiency.
How is a fast rate of contraction described?
- Low efficiency.
- High heat.
- Must overcome viscous forces in ECF.
How is a moderate rate of contraction described?
- Higher efficiency.
- High heat.
- Work being done and not trying to overcome viscosity.
What are the 2 types of muscle fibers?
- Slow/Type 1.
- Fast/Type 2.
What is the type of metabolism of slow twitch muscle?
Slow oxidative.
What color are slow twitch muscle?
Red.
What is the type of metabolism of fast twitch muscle Type IIa?
Fast, Oxidative, Glycolytic.
What is the type of metabolism of fast twitch muscle Type IIb?
Fast Glycolytic.
What color are both types of fast twitch muscle?
White.
What does the amount of each type of muscle depend upon?
- Environment.
- Genetics.
What is the relative diameter of slow-twitch muscle as compared to fast-twitch muscle?
Smaller.
What is the relative diameter of fast-twitch muscle as compared to slow-twitch muscle?
Larger.
What type of ATP synthesis does slow-twitch muscle utilize?
Aerobic.
What type of ATP synthesis does fast-twitch muscle utilize?
Anaerobic.
What is the fatigue resistance of slow-twitch muscle?
Good.
What is the fatigue resistance of fast-twitch muscle?
Poor.
What is the ATP hydrolysis rate of slow-twitch muscle?
Slow.
What is the ATP hydrolysis rate of fast-twitch muscle?
Fast.
What is the glycolysis capability of slow-twitch muscle?
Moderate
What is the glycolysis capability of fast-twitch muscle?
Fast.
What is the myoglobin content of slow-twitch muscle?
Abundant.
What is the myoglobin content of fast-twitch muscle?
Low.
