Question

relating to muscle tissue, what does the term involuntary mean?

• there are no nerve cells connected to this muscle tissue.
• some organ other than the brain stimulates this muscle tissue.
• the body does not consciously cause the contraction of involuntary muscle.
• only the cerebral cortex stimulates involuntary muscle tissue.
• i dont know yet

Explanation:

To determine the meaning of "involuntary" in muscle tissue:

• First option: Incorrect, as involuntary muscles (like smooth and cardiac) do have nerve connections (e.g., autonomic nervous system for smooth, cardiac has its own conduction system but still interacts with nerves).
• Second option: Incorrect, the brain (via autonomic nervous system) and other mechanisms (e.g., intrinsic cardiac conduction) regulate involuntary muscles, but the key is not about "some organ other than brain" being the sole stimulator.
• Third option: Correct. Involuntary muscle (smooth, cardiac) contractions happen without conscious control. For example, the heart beats or the stomach churns without us consciously deciding to do so.
• Fourth option: Incorrect, involuntary muscles are regulated by the autonomic nervous system (which includes parts beyond the cerebral cortex, like the brainstem, and also intrinsic mechanisms for cardiac muscle), not just the cerebral cortex.

Answer:

The option "The body does not consciously cause the contraction of involuntary muscle." (the third option among the answer choices)