Which of the Following Can Readily Cross the Blood-Brain Barrier

question 29

Multiple Choice

Which of the following can readily cross the blood-brain barrier?

• A) Cl⁻
• B) most anesthetics
• C) Na⁺
• D) none of these

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Definitions:

Preembryonic Development

The earliest phase of human development, from fertilization to the formation of the embryonic disc, which is before the actual embryo begins to form.

Morula

An early stage in embryonic development consisting of a solid ball of cells.

Endoderm

The innermost layer of cells or tissue of an embryo in early development, from which the digestive tract and associated structures develop.

Digestive Tract

The digestive tract is a series of hollow organs joined in a long, twisting tube from the mouth to the anus, where food is broken down into nutrients.