During Implantation

question 12

Multiple Choice

During implantation,

• A) the syncytial trophoblast erodes a path through the endometrium.
• B) the inner cell mass begins to form the placenta.
• C) maternal blood vessels in the endometrium are walled off from the blastocyst.
• D) the entire trophoblast becomes syncytial.
• E) the inner cell mass is temporarily deprived of nutrients.

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Definitions:

Extinction

In the field of behavioral psychology, the phenomenon where a learned response gradually becomes less frequent and ultimately vanishes because the previously associated stimulus is not presented alongside the original, unconditioned stimulus anymore.

Classical Conditioning

A process of learning through which two stimuli are habitually paired; the response, initially drawn out by the second stimulus, is eventually evoked by just the first stimulus.

Conditioned Stimulus

A previously neutral stimulus that, after becoming associated with an unconditioned stimulus, eventually triggers a conditioned response.

Unconditioned Stimulus

In classical conditioning, a stimulus that instinctively and automatically induces a response without previously being learned.