Muscles
Which of these events is necessary for the contraction of a muscle cell?
The shortening of myosin molecules
The hydrolysis of ATP to ADP and HPO42− in the myosin cross-bridge
Ca2+ binding to tropomyosin causing it to change shape
The movement of Ca2+ from the sarcoplasm into the sarcoplasmic reticulum
The hydrolysis of ATP to ADP and HPO42− in the myosin cross-bridge
The hydrolysis of ATP energises the cross-bridge (myosin molecules do not get shorter; calcium binds to troponin, not tropomyosin; calcium returns to the SR after contraction).
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Which of the following is the smallest unit in a muscle?A. Muscle fibre
B. Myosin
C. Fasciculus
D. Myofibril
What structures attach a muscle to a bone?
A. A tendon
B. A fasciculus
C. A sarcomere
D. An internal intercostal
Which muscle is located on the posterior part of the forearm?
A. Flexor digitorum superficialis
B. Flexor digitorum profundus
C. Extensor digitorum
D. Triceps brachii
Which of the following muscles is NOT named after its location in the body?
A. Deltoid
B. Extensor carpi ulnaris
C. Rectus abdominis
D. Biceps femoris
Which of the following muscles IS named after its location in the body?
A. Sartorius
B. Triceps brachii
C. Soleus
D. Trapezius
Which is the correct equation for anaerobic respiration in humans?
A. Glucose + lactic acid → carbon dioxide + water
B. Glucose → lactic acid + carbon dioxide
C. Glucose → lactic acid + (little energy)
D. Glucose→ lactic acid
The part of a skeletal muscle cell that is able to contract is called
A. Sarcoplasm
B. Sarcolemma
C. Sarcomere
D. Sarcoplasmic reticulum
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