Download Notes: Muscle Energy Pathways

Muscle Energy Pathways
There are 3 different pathways:
1. Direct phosphorylation
2. Aerobic respiration
3. Anaerobic glycolysis and lactic acid
formation
ATP & Muscle Contraction
•
•
Muscles use ATP
(adenosine triphosphate)
to contract.
Muscles store only about
4-6 seconds worth of ATP.
ATP & Muscle Contraction
Partner Lateral:
1. What is ATP used for in the muscles?
Specifically, what is going on with the
myofilaments?
Partner Medial:
2. In terms of time, how much ATP do we
have stored in our muscles?
Pathway 1: Direct Phosphorylation of
ADP by Creatine Phosphate
• Creatine Phosphate (CP) is found within muscle fibers.
• CP transfers its phosphate group to ADP (adenosine
diphosphate) to create ATP for muscle contraction
• Enough CP is in your muscles for about 20 – 30 seconds of
activity.
Partner Talk
• Explain the process by which Creatine
Phosphate makes ATP…
_____ + ______ = ATP
• In terms of time, how much Creatine
Phosphate do we have stored in our muscles?
2. Aerobic Respiration
• Requires a constant supply
of oxygen and nutrients.
• Converts Glucose and
Oxygen into ATP, Water
and Carbon Dioxide.
• Produces ATP very slowly;
Produces the most ATP (36
ATP) of all the Pathways.
Aerobic Respiration
•Partner Coffee:
What two things does Aerobic Respiration
require in order to work?
• Partner Tea:
How many ATP does Aerobic Respiration
produce and is it a fast or slow process?
3. Anaerobic Glycolysis
• Occurs when oxygen is not present
• Glucose is converted to Lactic Acid and ATP
• Makes ATP 2 ½ times faster than Aerobic Respiration,
however, only produces 2 ATP per Glucose molecule
• Provides ATP for 30 – 60 seconds of activity
Anaerobic Glycolysis
How does Anaerobic Glycolysis compare to Aerobic
Respiration in the following ways:
1. Requirement of Oxygen
2. Amount of ATP Produced
3. Speed of Producing ATP
• What else is produced by Anaerobic Glycolysis besides
ATP?
Muscle Fatigue & Oxygen Debt
• Muscle Fatigue – Muscle is
unable to contract even
though it is stimulated.
• Oxygen Debt – Inability to take
in oxygen fast enough to keep
muscles supplied with oxygen
• Recovery Period – Period of
time after activity when
oxygen, ATP, and CP levels are
restored. Indicated by heavy &
rapid breathing.
Muscle Fatigue & Oxygen Debt
Do a rock, paper, scissor with your partner.
•Partner Winner:
Explain Muscle Fatigue
•Partner Loser:
Explain Oxygen Debt and Recovery Period
Muscle Fatigue & Lactic Acid
• Muscle Fatigue is the result of a lack of
Oxygen and the production of Lactic Acid
• Lactic Acid build up, causes a decrease in ATP
Production.
• Recovery Period ‘pays back’ the Oxygen Debt.
Muscle Fatigue & Lactic Acid
Complete the following sentence:
Muscle Fatigue is caused by a lack of ______
and a production of ________
Which muscle energy pathway is being used
that causes muscle fatigue? Explain your
answer.
Answer these questions on page 16 of your notebook.
1. Which muscle energy pathway requires a constant
supply of oxygen to produce ATP?
2. Which muscle energy pathway produces Lactic Acid
as a byproduct?
3. Which muscle energy pathway provides ATP to the
muscle for the first 20-30 seconds of activity?
4. What is the name of the time following activity in
which the oxygen, ATP and CP levels are restored in
the body?
5. Make a pledge to your muscles to improve their
overall health/function. I _____, will…. Because…