What Is the Cause of Free Calcium in the Cytosol

question 3

Multiple Choice

What is the cause of free calcium in the cytosol that damages cell membranes by uncontrolled enzyme activation?

• A)Activation of endonuclease, which interferes with the binding of calcium to protein
• B)Activation of phospholipases, which degrade the proteins to which calcium normally binds
• C)An influx of phosphate ions, which compete with calcium for binding to proteins
• D)Depletion of ATP, which normally pumps calcium from the cell

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Definitions:

Optic Canal

A narrow passageway in the sphenoid bone of the skull through which the optic nerve and ophthalmic artery pass to the eye.

Agonist

A substance that fully activates the receptor it binds to, producing a maximal biological response.

Inferior Rectus

A muscle in the eye that controls downward eye movements, part of the extraocular muscles.

Medial Rectus

A muscle in the eye responsible for moving the eyeball towards the nose, part of the extraocular muscles.