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.
Answer:
Petiole
Explanation:
The petiole is the part of the leaf that attaches the leaf to the main stem of the plant. Depending on the leaf structure of the plant, some leaves may be devoid of a petiole, and be regarded as apetiolate.
Answer:
C
Explanation:
Ice-covered surfaces are highly reflective of the sun's rays therefore prevent those areas from warming as much as the areas where the ice is replaced with darker, less reflective surfaces which absorb heat and thus contribute more to global warming. Albedo is the percentage of radiation reflected by the earth's surface. Clear surfaces have greater albedo values than dark surfaces.
Answer:
High blood pressure is called hypertension or often referred to as the silent killer as it shows no symptoms at all.
Hope that helps!