At about 21 days, two ridges appear in the embryo and fold to make up the neural tube, which develops into the
A) nails, hair, and teeth.
B) digestive system, liver, and pancreas.
C) brain and spinal cord.
D) circulatory system, muscles, and skeleton.

Question

Quizplus · Accepted Answer

The neural tube forms early in embryonic development and eventually develops into the central nervous system, which includes the brain and spinal cord.

At About 21 Days, Two Ridges Appear in the Embryo