1. Pathogens have on their surface that bind to B cells with complementary .
2. B cells that bind to the pathogen divide, forming of identical cells with the same antigen.
3. Some cells of the clone develop into short-lived that secrete specific for the antigen.
4. Some cells develop into long-lived , which produce larger of memory and effector cells upon later exposure to the same antigen.

Explanation:

1. Pathogens have __antigens on their surface that bind to B cells with complementary _phagocyte.

2. B cells that bind to the pathogen divide, forming __plasma çells of identical cells with the same antigenantibodies

3. Some cells of the clone develop into short-lived ___cells that secrete ___antibodies specific for the antigen.

4. Some cells develop into long-lived ___cells, which produce larger ___immunology of memory and effector cells upon later exposure to the same antigen.

the calvin cycle has three stages. in stage 1, the enzyme rubisco incorporates carbon dioxide into an organic molecule. in stage 2, the organic molecule is reduced. in stage 3, rubp, the molecule that starts the cycle, is regenerated so that the cycle can continue

answer: carbon 14 can only be used to determine the age of the organisms that were once living, and igneous rocks are non living.

explanation: