Question

The two longitudinal ridges on the medulla oblongata where many descending fibers cross over are called the ________.

a. lateral horns
b. pyramids
c. olives
d. nuclei

Answer 1

pyramids

Step-by-step explanation:

• The medulla oblongata is a part of the hindbrain that makes up a part of the brain stem and is responsible for controlling the autonomic functions of the body system.
• The paired white matter structures present in the medulla oblongata are known as medullary pyramids.
• These pyramids consist of the motor fibers that belong to the corticospinal and the corticobulbar tracts.
• These pyramids are present on the ventral side of the medulla oblongata.

Answer 2

Pyramids.

Step-by-step explanation:

Medulla oblongata is one of portion of the hind brain that are responsible for controlling the autonomic functions of the body. Medulla oblongata lies to the inferior portion of the pons.

Pyramids are the two round mass of the white matter that are either located on the anterior of the median fissure. The nerve fibers are involved in the connection of the medulla to the pons, spinal cord and cerebral coretx. The fibres may gets cross over at pyramids.

Thus, the correct answer is option (b).