Select "Correct" If the Sentence Is Correctly Punctuated

question 21

Multiple Choice

Select "correct" if the sentence is correctly punctuated. Select "incorrect" if commas are missing or used incorrectly. Toby Liu asked you to call him right away.

• A) correct
• B) incorrect

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Definitions:

Blood-Brain Barrier

A selective semipermeable barrier formed by endothelial cells of the brain's capillaries that protects the brain from harmful substances and pathogens in the bloodstream.

CNS

The central nervous system, comprised of the brain and spinal cord, responsible for processing and sending out neural signals.

Myelin Sheath

A fatty layer that encases the axons of some neurons, significantly increasing the speed at which nerve impulses are conducted.

Cerebrospinal Fluid

A clear, colorless body fluid found in the brain and spinal cord, acting as a cushion and providing basic mechanical and immunological protection to the brain.