Which of the Following Occurs First During the Prenatal Period

question 127

Multiple Choice

Which of the following occurs first during the prenatal period of development?

• A) The external sexual characteristics become visible.
• B) The lower limbs become well developed.
• C) The lungs are capable of breathing air.
• D) The three major divisions of the brain-the hindbrain, the midbrain, and the forebrain-begin to differentiate.

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Definitions:

Electrical Signals

Impulses generated by the movement of ions, essential for the functioning of neurons and the communication within and between neural circuits.

Glycocalyx

A glycoprotein and glycolipid covering that surrounds the cell membranes of some bacteria, epithelia, and other cells.

Glycolipids

are lipids with a carbohydrate attached by a glycosidic linkage, primarily involved in cell recognition and membrane structure.

Glycoproteins

Proteins that have carbohydrate groups attached to the polypeptide chain, playing key roles in cellular functions such as cell-to-cell interaction.