On Flow Cytometric Analysis of a Sample of Fetal Thymus

question 91

Multiple Choice

On flow cytometric analysis of a sample of fetal thymus, a certain population of cells is identified that is positive for both CD4 and CD8 cell surface antigens.  These cells are best characterized as which of the following cells?

• A)Immature cortical T lymphocytes
• B)Mature cytotoxic T lymphocytes
• C)Mature helper T lymphocytes
• D)Antigen presenting cells
• E)Natural killer (NK) cells
• F)Thymic epithelial cells

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Definitions:

Fermentation

A metabolic process that converts sugar to acids, gases, or alcohol in the absence of oxygen, commonly used in the production of beer, wine, and bread.

Efficient

Achieving maximum productivity with minimum wasted effort or expense, often related to processes and systems.

Oxidized

Describes a substance that has lost electrons during a chemical reaction, often associated with the process of oxidation which can result in changes in energy, composition, or color.

Citric Acid Cycle

An array of chemical processes employed by all organisms requiring oxygen to unleash the energy held by oxidizing acetyl-CoA, which comes from carbohydrates, fats, and proteins.