At What Point in a Pregnancy Does the Heart Start

question 191

Multiple Choice

At what point in a pregnancy does the heart start beating?

• A) By 18 days after fertilization
• B) By the ninth week
• C) By the second trimester
• D) At the moment of birth

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Definitions:

Backward Conditioning

A conditioning procedure where the conditioned stimulus is presented after the unconditioned stimulus, making it less effective for learning associations.

US Presented

Typically means how specific concepts, ideas, or findings are introduced or demonstrated in the United States.

CS

In the context of classical conditioning, CS stands for Conditioned Stimulus, which is a previously neutral stimulus that, after association with an unconditioned stimulus, comes to trigger a conditioned response.

Second-order Conditioning

This is a process in which a stimulus that's already linked to a response becomes associated with another, new stimulus, creating a second conditioned stimulus.