Descending tracts
A) include the corticospinal tract.
B) contain axons of upper motor neurons that cross over to the other side of the spinal cord.
C) include the extrapyramidal tracts, which are involved in unconscious control of motor function.
D) contain upper motor neurons that modulate the activity of lower motor neurons.
E) have all of these properties.

Question

Quizplus · Accepted Answer

Descending tracts include the corticospinal tract, which is responsible for voluntary movement and contains axons of upper motor neurons that cross over to the other side of the spinal cord. They also include the extrapyramidal tracts, which are involved in unconscious control of motor function, and contain upper motor neurons that modulate the activity of lower motor neurons. Therefore, all of these properties are true of descending tracts.

Descending Tracts