The Rats in Dr

question 12

Multiple Choice

The rats in Dr. Rexington's learning laboratory are on an "FR-7" schedule of reinforcement. What does this mean?

• A)The rats will receive a food pellet after every seventh bar press.
• B)The rats will receive a food pellet after an average of every seven bar presses.
• C)The rats will receive a food pellet every seven minutes.
• D)The rats will receive a food pellet an average of every seven minutes.
• E)The rats will receive a food pellet every seven minutes, unless they press the bar seven times in a shorter period of time.

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Definitions:

MHC Markers

Major histocompatibility complex markers, proteins found on the surfaces of cells that help the immune system recognize foreign substances.

Antigens

Substances that when introduced into the body, trigger an immune response, often by the production of antibodies.

Retroviral Replication

The process by which retroviruses, including HIV, replicate by reverse transcribing their RNA into DNA and then integrating into the host cell genome.

AIDS

Acquired Immune Deficiency Syndrome, a disease of the human immune system caused by the human immunodeficiency virus (HIV).