The Integrin LFA-1 Is Constitutively Expressed on the Surface of Resting

question 12

Multiple Choice

The integrin LFA-1 is constitutively expressed on the surface of resting T cells. Yet, integrin-dependent T cell adhesion to antigen-presenting cells increases substantially following TCR stimulation. This increased integrin-dependent adhesion is mediated in part by:

• A) Increased synthesis of the LFA-1 protein
• B) Increased transport of intracellular pools of LFA-1 to the cell surface
• C) LFA-1 conversion to a high affinity binding state
• D) Increased phosphorylation of the LFA-1 cytoplasmic tail
• E) Activation of cdc42 and WASp

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Definitions:

Clitellum

A thickened, glandular section of the body found in earthworms and some other annelids, crucial for reproduction.

Fertilization

Fusion of sperm and egg nuclei, producing a zygote that develops into a new individual.

Cephalopods

A class of marine molluscs that includes octopuses, squids, and cuttlefish, known for their intelligence and ability to change color.

Visceral Mass

The part of a mollusk's body that contains most of the internal organs.