B. they are both unicellular
The answer would be Oxygen
Approximately 10,000 years ago.
No because mutations can lead to bad things
Answer:
Fab or fragment antigen binding
Explanation:
Treating the antibody with a protease can cleave this region, producing Fab. that include the variable ends of an antibody. Material used for the studies .The constant region determines the mechanism used to destroy antigen. Antibodies are divided into five major classes, IgM, IgG, Iga, IgD, and IgE, based on their constant region structure and immune function.