Answer:
a blood protein
Explanation:
a blood protein produced in response to and counteracting a specific antigen. Antibodies combine chemically with substances which the body recognizes as alien, such as bacteria, viruses, and foreign substances in the blood.
A. enzymes
Most chemical reaction in the metabolic pathways need to interact with an enzyme in order to occur.
Frequency of action potentials hopes this helps :))
2 and 3 only is the correct answer ! Hope this helped
