The Cranial Base Is Determined by Drawing a Line from the Nasal

question 31

Multiple Choice

The cranial base is determined by drawing a line from the nasal bone (nasion) to which structure?

• A) External auditory canal
• B) Tragus of the ear
• C) Petrous portion of the temporal bone
• D) Sella turcica

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Definitions:

Brainstem

The lower extension of the brain where it connects to the spinal cord, responsible for controlling many basic life functions such as breathing and heart rate.

Spinal Cord

A long, thin, tubular structure made up of nervous tissue, extending from the brainstem down the vertebral column, playing a critical role in transmitting neural signals between the brain and the rest of the body.

Pyramids

Structures in the medulla oblongata of the brain involved in the transmission of motor signals to the spinal cord.

Descending Tracts

These are pathways in the central nervous system that transmit motor signals from the brain down the spinal cord to the muscles or glands.