Muscles
Which event causes the thick filament to slide over the thin filament (i.e. the “power stroke”) during muscle contraction?
The attachment of Ca ions to troponin
The hydrolysis of ATP to ADP, inorganic phosphate and energy
The engagement of the head of the myosin cross-bridge with its binding site on actin
The attachment of a molecule of ATP to the head of myosin’s cross-bridge
The engagement of the head of the myosin cross-bridge with its binding site on actin
The attachment of the already energised cross-bridge to its binding site stimulates the head to swivel and so cause the filaments to slide over each other. Choice A causes the binding site to be exposed. Choice B energises the cross-bridge. Choice D causes detachment of the cross-bridge.
The engagement of the head of the myosin cross-bridge with its binding site on actin The attachment of the already energised cross-bridge to its binding site stimulates the head to swivel and so cause the filaments to slide over each other. Choice A causes the binding site to be exposed. Choice B energises the cross-bridge. Choice D causes detachment of the cross-bridge.
Related posts
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 โ carbon dioxide + water
B. Glucose โ lactic acid + carbon dioxide
C. Glucose โ lactic acid + (little energy)
D. Glucoseโ 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
Leave a Reply