When a Sarcomere Is at Rest,the Myosin Binding Sites on Actin

question 4

Multiple Choice

When a sarcomere is at rest,the myosin binding sites on actin are blocked by _____.  

• A) phosphorous
• B) sodium
• C) tropomyosin
• D) the myosin heads
• E) AMP

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Definitions:

Cauda Equina

A bundle of spinal nerves and spinal nerve rootlets, resembling a horse's tail, located at the lower end of the spinal cord.

Filium Terminale

The filum terminale is a slender filament of connective tissue that extends from the tip of the spinal cord to the coccyx, anchoring the spinal cord in place.

Conus Medullaris

The tapered, lower end of the spinal cord, located around the first lumbar vertebra, marking the transition from the spinal cord to the cauda equina.

Cervical Enlargement

A widening in the upper part of the spinal cord that supplies nerves to the shoulders, arms, and hands.