Examination of a tissue sample from the central nervous system reveals many darkly pigmented cells.This tissue probably came from the
A)nucleus gracilis.
B)nucleus cuneatus.
C)motor cortex.
D)substantia nigra.
E)red nucleus.

Question

Quizplus · Accepted Answer

The substantia nigra is a region in the midbrain that contains darkly pigmented neurons. These neurons produce dopamine, which plays an important role in the control of movement. Parkinson's disease is characterized by the degeneration of dopamine-producing neurons in the substantia nigra, leading to motor dysfunction. Therefore, the presence of darkly pigmented cells in a tissue sample is suggestive of the substantia nigra.

Examination of a Tissue Sample from the Central Nervous System