Why Are Functions of T-Lymphocytes Referred to as "Cell-Mediated" Immunity

question 31

Multiple Choice

Why are functions of T-lymphocytes referred to as "cell-mediated" immunity?

• A) Because T-lymphocytes are cells and not just plasma proteins
• B) Because T-lymphocytes work against antigens associated with cells
• C) Because T-lymphocytes work only against single-celled infectious agents
• D) Because T-lymphocytes must activate other classes of cells in order to have any effect

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Definitions:

Relay Contacts

The contacts of a relay that are either opened or closed according to the condition of the relay coil. Relay contacts are designated as either normally open or normally closed in design.

Coil

Represents the output of a programmable logic controller. In the output devices, it is the electrical coil that, when energized, changes the status of its corresponding contacts.

Reed Switches

Electromechanical devices that open or close contacts in response to a magnetic field.

Magnetism

A physical phenomenon produced by the motion of electric charge, which results in attractive and repulsive forces between objects.