Answer:
Innate immunity is a non-specific immune system which provides defence against any pathogenic microorganism in early stages. It includes physical barrier such as skin, chemical barriers such as saliva, tears, et cetera, phagocytic cells such as macrophages, et cetera.
Acquired immune system is the one which develops after exposure to pathogen or antigen. It is highly specific in nature. It includes B-lymphocytes and T-lymphocytes. It includes the production of antibodies.
Vaccines are used to develop acquired immunity in people. The process is termed as vaccination or immunisation. Heat-killed or weakened pathogen or antigen is inserted into a person after which a person develops antibodies and memory cells against that pathogen or disease. So, the immune system acts more vigorously against that pathogen in secondary infection.
Thus, a person becomes immunised.
Correct answer: B). The phagocytotic barrier, which is a part of innate immunity
The scenario represents the phagocytosis, which is a type of endocytosis by which the cell engulfs microbial pathogens. The main cells of the immune system that are involved in phagocytosis include macrophages, neutrophils, and dendric cells.
It is a mechanism which is used by the immune system to kill and processing of antigen that play an important role in innate immune response.
Hence, the correct answer would be option B.
<span> It is due to the excessive pressure that is created over </span>oxygen<span>.</span>
Answer:
one which is able to express itself outwardly in the presence of a recessive allele
Explanation: