Section 5.5-5.6 Quiz

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. Identify possible opportunities for a productive β-chain rearrangement.

β-chain V segment rearranging with a β1 DJ segment (D1J1) correct incorrect

β-chain D segment rearranging with a β1 VJ segment (V1J1) correct incorrect

β-chain D segment rearranging with a β2 VJ segment (V2J2) correct incorrect

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. Recombination of the α-chain locus occurs before the β-chain checkpoint has been passed.

True correct incorrect

False correct incorrect

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. Identify the true statement about the pre-T α chain (pTα) in the context of T-cell development.

It assembles with the rearranged γδ chain. correct incorrect

It prevents any downstream signaling upon T-cell receptor engagement. correct incorrect

It assembles with the CD3 complex and ensures that a functioning T-cell receptor can be formed later. correct incorrect

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. What happens to the large number of thymocytes that do not pass the α- and β-chain checkpoints?

They begin to express the coreceptors CD4 and CD8 and become double-positive thymocytes. correct incorrect

They form the pre-T α chain complex. correct incorrect

They are programmed to become pre-T cells. correct incorrect

They are programmed for cellular death and removal by resident macrophages. correct incorrect

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. Rearrangement of the α chain must be tested to ensure that the chain does not become a subunit of the T-cell receptor.

True correct incorrect

False correct incorrect

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. The α chain is tested in the endoplasmic reticulum membrane.

True correct incorrect

False correct incorrect