<span>Norepinephrine uses the Second
Messenger System, which means, cells signal to each other what molecules have
been released that will trigger a physiological reaction. </span>
<span>
This phenomenon is activated after the ligand (ion or molecule) is bonded to its receptor
(protein molecule), creating a variation that causes a chain-reaction, that will
finally activate the Second Messenger. The latter will activate intercellular
molecules that will be able to control the cell’s activity. </span>
During the process of biological magnification , the concentration of pollutants, such as DDT or mercury, is multiplied as it passes up a food chain.
Answer:
All errors described will result in a negative result
Explanation:
The enzyme-linked immunosorbent assay (ELISA), is a test used to detect and measure antibodies, antigens and proteins in the blood. An ELISA test uses antibodies and/or antigens that are coupled to an easily-assayed enzyme, thereby this approach combines antibody specificity with the sensitivity of simple enzyme assays. ELISA test involves an antibody or antigen that reacts to form an antigen-antibody complex, where such reaction is interpreted as a positive result. The negative results are evidenced by the lack of reaction, which may be caused by some error during the chain of reactions in the ELISA test: antigen >> primary antibody (reaction) >> functional secondary antibody (reaction) >> conjugated enzyme (reaction) >> functional substrate.
