Answer:
A Mutation is an agent of substance that can bring about a permanent alteration to the physical composition of a DNA gene such that the genetic message is changed.
Explanation:
Answer:
Presence of specific antigen receptors on the surface of Immunocompetent B and T cells make them to generate immune response against specific antigens only.
Explanation:
The cellular and antibody-mediated immune responses are specific in nature. This means these immune responses are generated for particular foreign molecules or antigens only. These immune responses include B and T lymphocytes. Before T cells leave the thymus or B cells leave the red bone marrow, they develop immunocompetence. Immunocompetence is the ability to carry out adaptive immune responses. During this process. B cells and T cells make distinctive proteins and insert them into their plasma membranes. Some of these proteins function as antigen receptors capable of recognizing specific antigens. This is why the B and T cell-mediated third line of defense are specific in nature.
For example, antibody-mediated immune responses generate the memory cells for most previously encountered antigens to ensure the generation of more rapid and vigorous response during any further encounter with the same antigen.
Answer:
Preformed vitamin A is found in foods from animal sources, including dairy products, eggs, fish, and organ meats [1,2]. Provitamin A carotenoids are plant pigments that the body converts into vitamin A in the intestine [1,3].
Answer:
D.)
Explanation:
Cladograms can compare more animals at one time than traditional classification methods.
Prokaryotes taht obtain energy from sunlight are called PHOTOTROPH. These prokaryotes use energy from the sun to synthesize organic compound for food and to carry out other metabolic processes. The energy synthesized from the sun is in form of ATP.
