Although the Heart Does Not Require the Nervous System to Initiate

question 198

Multiple Choice

Although the heart does not require the nervous system to initiate contraction events:

• A) it is sympathetically innervated via cardiac nerve fibers.
• B) it is parasympathetically innervated by vagus nerve fibers.
• C) it is innervated by the phrenic nerve.
• D) it is innervated by the sympathetic division of the autonomic nervous system only.
• E) both (a) and (b) above.

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Definitions:

Botulin Toxin

Botulin Toxin is a powerful neurotoxin produced by the bacterium Clostridium botulinum, used medically to treat a variety of conditions by causing temporary muscle paralysis.

Acetylcholine Antagonist

Substances that block the action of acetylcholine, a key neurotransmitter in the nervous system, affecting various bodily functions.

Agonist

Substance that enhances neurotransmitter function.

Antagonist

Substance that blocks neurotransmitter function.