Which Is the First Signal in the Activation of a T

question 39

Multiple Choice

Which is the first signal in the activation of a T cell?

• A) the fusion of antigenic peptide fragments and major histocompatibility complex (MHC) proteins
• B) a T cell receptor recognizing an antigen using the CD4 protein
• C) a T cell undergoing clonal selection
• D) the exocytosis of the antigen-major histocompatibility complex (MHC) protein compound into the plasma membrane
• E) a T cell receptor recognizing a peptide fragment of a self-protein

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Definitions:

Spinal Cord

A long, thin, tubular structure made up of nervous tissue, which extends from the brain, downward through the vertebral column, facilitating communication between the brain and the body.

Sternoclavicular Joint

A pivotal joint at the base of the neck, where the clavicle (collarbone) meets the sternum (breastbone) at the top of the chest.

Glenohumeral Joint

The ball-and-socket joint of the shoulder, allowing a wide range of movement of the arm.

Appendicular Skeleton

The portion of the skeleton consisting of the upper limbs and the lower limbs and their girdles.