Innate immunity is characterized by:
A. It is present since birth
B. It prevents the microbes to enter in our body
C. It can produce antibody
D. Hydrochloric acid of stomach is a physiological barrier
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → A, B and D only
Innate immunity is the non-specific defence that a person has from birth. It works through four kinds of barriers. Physical barriers are the skin and mucus. Physiological barriers are the acid in the stomach, saliva and tears. Cellular barriers are cells such as neutrophils, monocytes and natural killer cells. Cytokine barriers are the interferons.
A. It is present since birth — Correct. Innate immunity is present at the time of birth.
B. It prevents the microbes to enter in our body — Correct. Its barriers, such as the skin and mucus, stop microbes from entering the body.
C. It can produce antibody — Incorrect. Antibodies are made by B-lymphocytes. They belong to acquired immunity, which is specific and develops after meeting a pathogen.
D. Hydrochloric acid of stomach is a physiological barrier — Correct. The acid in the stomach stops the growth of microbes.
NCERT Extract:
Innate Immunity – “Innate immunity is non-specific type of defence, that is present at the time of birth. This is accomplished by providing different types of barriers to the entry of the foreign agents into our body. Innate immunity consist of four types of barriers. These are — …”
Innate Immunity – “… (i) Physical barriers : Skin on our body is the main barrier which prevents entry of the micro-organisms. Mucus coating of the epithelium lining the respiratory, gastrointestinal and urogenital tracts also help in trapping microbes entering our body.”
Innate Immunity – “… (ii) Physiological barriers : Acid in the stomach, saliva in the mouth, tears from eyes–all prevent microbial growth.”