Classification

question 12

Multiple Choice

Classification. Respond to the following statements with reference to the five types of white cells listed below.
-These cells recognize cell surface antigens and initiate the proliferation of lymphocytes.

• A)macrophages
• B)helper T cells
• C)B cells
• D)cytotoxic T cells
• E)natural killer cells

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Definitions:

Refractory Period

A period immediately following stimulation during which a nerve or muscle is unresponsive to further stimulation.

Action Potential

A brief electrical impulse that enables the transmission of signals along the neuron, crucial for nerve impulse propagation.

Above-Threshold

Pertaining to a stimulus strength that is sufficient enough to be detected or to produce a response.

Depolarizing Current

An electrical current that reduces the membrane potential of a neuron, making it more likely to fire an action potential.