Refer to the Figure Showing an Acorn Worm (Top) and Pterobranchs

question 76

Multiple Choice

Refer to the figure showing an acorn worm (top) and pterobranchs (bottom) . Which of the following is a feature or features of pterobranchs but not of acorn worms?

• A) Proboscis
• B) Collar
• C) Tentacles
• D) Trunk
• E) Tube feet

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Definitions:

Brain Stem

The part of the brain that connects the spinal cord with the forebrain and cerebrum, crucial for regulating basic life functions such as breathing and heart rate.

Myelin

A fatty substance that surrounds and insulates the nerve fibers in the central and peripheral nervous systems, facilitating the rapid transmission of nerve impulses.

Axons

Long, slender projections of nerve cells that conduct electrical impulses away from the neuron's cell body to other neurons, muscles, or glands.

Nerve Impulses

Electrical signals that are transmitted along nerve fibers in the nervous system.