The "Selectivity" of a Particular Ion Channel Refers to Its

question 64

Multiple Choice

The "selectivity" of a particular ion channel refers to its

• A) permitting passage by positive but not negative ions.
• B) permitting passage by negative but not positive ions.
• C) ability to change its size depending on the ion needing transport.
• D) binding with only one type of neurotransmitter.
• E) permitting passage only to a specific ion.

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Definitions:

Duodenum

The first section of the small intestine, immediately beyond the stomach, which plays a critical role in digestion by receiving bile and pancreatic juices.

Jejunum

The middle section of the small intestine, between the duodenum and ileum, which is responsible for the absorption of nutrients.

Cecum

The first part of the large intestine, into which the ileum opens from one side, and is shaped like a pouch.

Ileum

The third and final portion of the small intestine, where absorption of nutrients and minerals concludes.