By the Third Week After Conception a Sheet of Primitive

question 140

Multiple Choice

By the third week after conception a sheet of primitive neural cells forms a:

• A)hollow tube called the neural tube.
• B)cavity called the ventricle.
• C)hollow tube called the stem cell.
• D)cavity called the amniotic sac.

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Definitions:

Negative Reinforcement

A behavioral principle where the removal of an unpleasant stimulus following a behavior increases the likelihood of that behavior being repeated.

Positive Reinforcement

An increase in the future frequency of a behavior due to the addition of a stimulus immediately following a response.

Negative Reinforcement

A behavioral principle where the removal of an unpleasant stimulus strengthens a behavior, increasing its occurrence.

Negative Punishment

A behavioral control method where the removal of a desirable stimulus decreases the likelihood of a behavior recurring.