Suppose a researcher calculates the dissociation constant of the binding between two immunoglobulin G (IgG) antibodies, IgG‑1 and IgG‑2, and several antigens. He calculates the dissociation constant ( K d ) of each IgG and antigen based on what concentration of the antigen causes half‑maximal saturation of the IgG molecules. The K d value reveals the affinity between the IgG molecules and the antigens. He needs to determine which antigen specifically binds IgG‑1 or IgG‑2 based on K d .

Assuming that the Kd values of A are 9.1x10 (-5), B 3.2x10 (-11), and C 2.7x10 (-6) for IgG1 immunoglobulin, antigen A is considered to have the least affinity for the antibody. , then followed by antigen C and lastly B.

Regarding the Kd of the antigens with respect to IgG2, they are: A 4.0x10 (-10) B 7.4x10 (-10) and C 1.8x10 (-11), considering that the antigen that has the least affinity to said antibody is the B, then followed by A and finally C

Explanation:

It is important to know that the dissociation constant is inversely proportional to Kd, that is, to the association constant, this means that it is indirectly proportional to affinity as well.

This is why the dissociation constant = 1 / Kd.

the correct option is c.

isotopes refers to different forms of the same element with the same atomic number but different mass number as a result of difference in their neutron numbers. isotopes have different relative atomic mass but share the same chemical properties.