One is able to intelligently debate issues.
Answer;
Cycilc AMP
Explanation;
-Second messengers are molecules that relay signals received at receptors on the cell surface; such as the arrival of protein hormones, growth factors, etc., to target molecules in the cytosol and/or nucleus.
-Many of the chemical messengers such as hormones, that transmit messages from one cell to another never enter the target cell, these molecules are known as first messengers which work by binding to a specific receptor on the cell surface. The receptor then stimulates or inhibits the production of a so-called second messenger within the cell.
-The second messenger are small molecules such as Cyclic AMP, which activate an effector within a cell.
I had to look for the missing options so here is my answer:
A receptor protein is a kind of intracellular protein which activates its function when it receives signals from outside of the cell. One of the responses it does is some changes in the tissues. Receptor proteins possess multiple functions inside the cell, and the one that is not included is <span>preventing cytoplasmic reconstitution. </span>
i think it is 2 but i could be wrong