The Four-Chambered Heart First Evolved Among The

question 73

Multiple Choice

The four-chambered heart first evolved among the:

• A) arthropods.
• B) birds.
• C) nonavian reptiles.
• D) mammals.
• E) fishes.

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Definitions:

Unconditioned Response

An automatic, natural reaction to a stimulus that occurs without the need for prior learning or conditioning.

Sensitization

The process by which an individual becomes more sensitive to a stimulus after being exposed to it, often leading to heightened responses.

Disinhibition

A reduction in restraint or inhibition which can lead to uninhibited or impulsive behavior due to various factors including alcohol, drugs, or certain mental health conditions.

Conditioned Stimulus

An initially neutral stimulus that, after being associated with an unconditioned stimulus, elicits a conditioned response.