Mutations in the Gene for Troponin Can Result in the Production

question 37

Multiple Choice

Mutations in the gene for troponin can result in the production of the troponin protein, which has varying affinities for Ca2+ ions. Suppose that in a muscle cell a mutant troponin is expressed that has such a high affinity for Ca2+ ions that once they bind to troponin they cannot unbind. What will likely happen in this muscle cell?

• A) Myosin heads will not bind to actin after action potentials stop being received.
• B) Myosin heads will bind to actin after action potentials stop being received.
• C) Tropomyosin will not move to expose myosin binding sites.
• D) Cross-bridges will form between myosin and tropomyosin.

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Definitions:

Parietal Lobe

A region of the brain associated with processing sensory information concerning the body's position and navigation.

Frontal Lobe

The frontal lobe is a region in the brain involved in decision making, problem solving, control of purposeful behaviors, consciousness, and emotions.

Temporal Lobe

A region of the cerebrum responsible for hearing, understanding language, and storing memories.

Occipital Lobe

The region of the brain located at the back of the head, responsible for processing visual information.