What Do You Know About a Person Who Has a Recessive

question 18

Multiple Choice

What do you know about a person who has a recessive allele for a particular trait but who does not show that trait?

• A) He or she is heterozygous for that trait.
• B) His or her alleles are codominant.
• C) Two recessive alleles are present.
• D) A gene mutation has occurred.

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Definitions:

Glutamate

A major excitatory neurotransmitter in the brain, involved in memory, learning, and the regulation of the nervous system.

Neurotransmitter

Chemical substances released at the end of a nerve fiber by the arrival of a nerve impulse, which, by diffusing across the synapse or junction, causes the transfer of the impulse to another nerve fiber, a muscle fiber, or some other structure.

Memory Formation

The process by which experiences are encoded, stored, and retrieved in the brain.

Acetylcholine

A neurotransmitter in both the peripheral and central nervous systems that is involved in muscle activation, memory formation, and learning.