The Action Potential Is Generated When a Stimulus

question 25

Multiple Choice

The action potential is generated when a stimulus

• A) opens sodium channels.
• B) opens voltage-gated potassium channels.
• C) causes the interior of the cell to become more negative.
• D) blocks the entry of sodium into the cell.

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Definitions:

Proliferative Phase

A phase of the menstrual cycle in which the lining of the uterus thickens in preparation for potential pregnancy, driven by the hormone estrogen.

Menstrual Phase

The phase in the menstrual cycle where the uterine lining is shed, resulting in menstrual bleeding.

Endometrium

The inner lining of the uterus, which thickens during the menstrual cycle in preparation for implantation of a fertilized egg or is shed during menstruation if no pregnancy occurs.

Embryo Implantation

The process by which a fertilized egg attaches itself to the lining of the uterus to begin pregnancy.