Download METHODS OF PROVIDING ENERGY for MUSCLE ACTIVITY

Human Anatomy & Physiology – Newark High School – Mr. Taylor
METHODS OF PROVIDING ENERGY FOR
MUSCLE ACTIVITY
Direct Phosphorylation of ADP by
Creatine Phosphate (CP)
• Fastest mechanism for regenerating ATP
• Creatine phosphate found only in muscle cells
• Supply is quickly exhausted (about 20 seconds)
Aerobic Respiration
• Uses oxygen during metabolic pathway
• Fairly slow and requires continuous supply of
Oxygen
• Glucose ( C6 H12 O6 ) broken down to Carbon
Dioxide and Water
• Energy released as bonds are broken captured
as ATP
• 36 ATP for each glucose
Anaerobic glycolysis and lactic acid
formation
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Does not use oxygen
Glucose gets broken down to pyruvic acid
Small amounts captured as ATP (2 ATP per 1 glucose)
Once oxygen stores depleted, pyruvic acid converts to
lactic acid
• 2 ½ times faster than aerobic respiration
• Provides most of the ATP needed for 30 to 40 seconds
worth
• Requires large amounts of glucose and lactic acid
results in fatigue
Muscle Fatigue and Oxygen Debt
• Muscles tire quickly and contract weakly when O2
levels are low
• Oxygen debt occurs during long periods of activity
• O2 supply is not equal to the demands for it
• Lactic acid is produced and the anaerobic mechanism is
utilized
• ATP stores run low and fatigue sets in
• Debt is paid off during recovery through rapid
breathing
• Lactic acid is removed; CP and ATP is regenerated in
time