How does the immune system recognize diverse possible antigens? •how do antibodies simultaneously recognize a huge variety of antigens and carry out a limited number of effector functions? •what is v(d)j recombination? what do the letters (and parentheses) signify? •what is the 12/23 rule? •what are rag-1/2 and tdt? what do they recognize? what do they do? •what changes at the ig loci are required to switch from membrane-bound to secreted ig?

check the explanations

Explanation:

1.- The immune system recognize antigens because both are complementary proteins, they match like in a puzzle, just to the exact shape and not to another that is similar.

2.- Since each antibody has a different shape, that is unique, so it will recognize just one kind of protein.

3.- Variable (diversity) joining, is a genetic recombination that occurs in the lymphocytes to produce antibodies.

4.- The rule 12/23 is apply when a protein is in the process of recombination of the DNA, if the recombination occurs in just one chain so just 12 basepairs are working, but if there are 2 strains, then 23 basepairs are included.

5.- The recombination activation gene (RAG)  codify enzymes for the reorder and recombination of the inmunoglobine and the linphocytes T.

6.- Is a Loci in the genetic code for a cancer gene, could be turn "off" and when is in contact with some factors could be "on" and produce cancer.

here is the answer

water, ice, acids, salts, plants, animals, and changes in temperature are all agents of weathering. weathering is the breaking down or dissolving of rocks and minerals on earths surface. once a rock has been broken down, a process called erosion transports the bits of rock and minerals away.