The PNS Axons of Lower Vertebrates

question 143

Multiple Choice

The PNS axons of lower vertebrates

• A) can regenerate, but they do so inaccurately.
• B) can regenerate accurately only if they grow into Schwann-cell sheaths.
• C) are usually unmyelinated.
• D) can regenerate accurately even when they do not grow back through their original Schwann-cell sheaths.
• E) cannot regenerate.

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Definitions:

Phagocytic Cells

Cells that have the ability to engulf and absorb bacteria, other foreign particles, and sometimes dead cells, as part of the immune response.

Monokines

A subset of cytokines, which are proteins secreted by immune cells that impact the behavior of other cells, typically involved in inflammatory and immune responses.

Edema

An excessive buildup of fluid in body tissue.

Vessels

Structures such as veins, arteries, and ducts that carry fluids like blood or lymph through the body.