In the Process of Swallowing,food Cannot Normally Enter the Trachea

question 32

Multiple Choice

In the process of swallowing,food cannot normally enter the trachea because the ________.

• A)tongue directs the flow of food down the esophagus and away from the trachea
• B)esophageal sphincter shuts off the passage to the larynx
• C)epiglottis covers the larynx
• D)trachea does not connect to the esophagus

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Definitions:

T-Cell Receptor

A molecule found on the surface of T cells that is responsible for recognizing fragments of antigens as peptides bound to major histocompatibility complex (MHC) molecules.

CD8 Glycoprotein

A surface protein found on certain immune cells, such as cytotoxic T cells, involved in the immune response.

CD4 Glycoprotein

A protein on the surface of immune cells, such as T helper cells, that is involved in initiating the immune response.

Cytotoxic T

A type of lymphocyte (T cell) that kills cancer cells, cells that are infected (particularly with viruses), or cells that are damaged in other ways.