Which of the following statements is true regarding t cell receptors? (select all that apply.) they are formed by the rearrangement of v, j, c, and d gene segments. they contain variable and constant regions. they can be found in the bloodstream independent of t cells. they recognize antigen-mhc complexes. they are composed of two heavy (h) chains and two light (l) chains.

The true statements about he T cell receptors are 1, 2 and 4.

T cell receptors are the molecules found on the surface of the T lymphocytes. V(D)J recombination is the unique mechanism of genetic recombination that occurs only in the lymphocytes during the early stages of T and B cell maturation resulting in the T cell receptors. They recognize antigen fragments bound to MHC molecules. Majority of the T cell receptors consists of an alpha chain and a beta chain and a few with gamma and delta chains. Each chain is composed of a variable and a constant region. Within these chains are the complementary determining regions (CDRs) which determine the antigen to which the T cell receptor will bind.  

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