The Molecule Indicated on This Illustration of the First Signal

question 58

Multiple Choice

The molecule indicated on this illustration of the first signal during the activation of a cytotoxic T cell (T_C) must be

• A) Class I MHC.
• B) Class II MHC.
• C) a CD8 molecule.
• D) a B7 protein.

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Definitions:

Neutral Stimulus

In conditioning, a stimulus that initially elicits no specific response other than focusing attention, which can eventually elicit a conditioned response when paired with an unconditioned stimulus.

Unconditioned Response

A natural, unlearned reaction to an unconditioned stimulus, part of classical conditioning theory.

Unconditional Reinforcement

A form of reinforcement in operant conditioning that is given consistently every time a desired response is made.

Unconditioned Response

An automatic, natural reaction to a stimulus that does not depend on prior learning.