• Understand the energy sources required for muscle contraction
• Describe 3 types of muscle fibre and understand their different properties and
functions.
• Understand the different types of skeletal muscle function (twitch, twitches and tetanus) by the motor unit.
• Summarise key effects of exercise & fatigue on muscle physiology
Choose the correct statements about sources of energy for skeletal muscle contraction
Answer
ATP can be recycled and the stores are long lasting.
ATP is limited in it's stores and only fuels contraction for a few seconds.
CP, creatine phosphate, is stored in the muscle.
Pi is a product of ATP hydrylosis, called inorganic phosphate.
Energy from CP breakdown is used to resynthesize ATP.
With CP you can have a contraction up to 50 s.
The third back up system for energy generation in muscle is the metabolism of glucose, which can be aerobic or anaerobic.
The breakdown of glucose is anabolic and therefore produces free energy to resynthesize CP and ATP.
Question 2
Question
Anaerobic metabolism is the breakdown of glucose via glycolysis to make ATP.
Answer
True
False
Question 3
Question
Aerobic metabolism takes pyruvate from glycolysis to make Acetyl CoA, and then uses oxygen, to produce less ATP than anaerobic metabolism.
Answer
True
False
Question 4
Question
Choose the incorrect statement about anaerobic metabolism.
Answer
No O2 is used.
It is slow.
It is a short term form of energy production.
It is the result of glycolysis.
Question 5
Question
Choose the incorrect statement about aerobic metabolism.
Answer
It is faster than anaerobic metabolism.
O2 is used.
It is facilitated by a process called oxidative phosphorylation.
It is a long term and stable process.
Question 6
Question
Which stage of skeletal muscle movement uses the MOST ATP?
Answer
Excitation
Relaxation
Contraction
Question 7
Question
Oxygen binding to iron appears red. Iron is a central part of myoglobin in the muscles, so the more oxygen present in the muscle, the redder the colour appears.
Answer
True
False
Question 8
Question
Choose the correct statement.
Answer
Red muscle fibres are high in myoglobin and low in aerobic enzymes.
Red muscle fibres are high in myoglobin and high in aerobic enzymes.
White muscle fibres are high in myoglobin and low in aerobic enzymes.
White muscle fibres are low in myoglobin and high in aerobic enzymes.
Question 9
Question
Which type of muscle fibre would a marathon runner/endurance athlete develop?
Answer
More white and intermediate fibres.
More red and intermediate fibres.
Question 10
Question
Choose the incorrect statement about muscle contractions.
Answer
A twitch is a single muscle contraction.
The calcium level in the sarcoplasm lasts longer than the muscle tension.
A series of spaced twitches with increasing tension amplitude is a treppe.
Complete tetanus is a series of closely spaced twitches summated where you cannot differentiate individual twitches.
Question 11
Question
Which of these is NOT responsible for increasing amplitudes in a treppe?
Answer
Increasing and sustained calcium levels in the sarcoplasm
Increased sensitivity to calcium of myosin and actin
Heat
Cross bridge volatility
Question 12
Question
Choose the correct statements about muscle training.
Answer
By strength training you increase the number of muscle fibres.
By strength training you increase the number of contractile filaments.
Hypertrophy is the decreasing of contractile filaments.
Increasing the number of contractile filaments means you rely more on aerobic metabolism.
Endurance training increases the number of blood vessels (capillaries), mitochondria, and aerobic enzymes in muscle.