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Human Health and Disease — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYHuman Health and Disease4 Marks
Question
Explain innate immunity in detail
✓

Answer

→Innate immunity is non-specific immunity, which is present at the time of birth.
1) Physical barrier :
→Our skin is the main physical barrier that prevents the entry of microorganisms.
→Mucous membrane lining the respiratory tract, gastrointestinal tract and urinary tract also helps to prevent germs from entering the body.
2) Physiological barrier:
→Acid in the stomach, saliva in the mouth, tears in the eyes etc. inhibit the growth of pathogens.
3) Cellular Barrier :
→Some white blood cells [WBCs] in our body, such as polymorphonuclear leukocytes and natural killer cells, a type of lymphoid cell in the blood, can feed on and destroy microbes.
(4)Cytokine barrier:
→Virus-infected cells secrete proteins called interferons, which protect other uninfected cells from virus infection.

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