Match List-I with List-II
| LIST-I | LIST-II |
|---|---|
| Innate immunity barriers | Examples |
| (A) Physical barriers | (I) Interferons |
| (B) Physiological barriers | (II) Neutrophils and monocytes |
| (C) Cellular barriers | (III) Mucus coating epithelium lining in respiratory tract |
| (D) Cytokine barriers | (IV) Saliva and tears |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → (A) - (III), (B) - (IV), (C) - (II), (D) - (I)
(A) Physical barriers — this matches (III) Mucus coating epithelium lining in respiratory tract. A physical barrier blocks the entry of microbes. The skin is the main one, and the mucus lining the respiratory, digestive and urogenital tracts traps microbes.
(B) Physiological barriers — this matches (IV) Saliva and tears. These are body fluids and secretions that stop microbes from growing, like the acid in the stomach, saliva in the mouth and tears from the eyes.
(C) Cellular barriers — this matches (II) Neutrophils and monocytes. These are white blood cells that swallow (phagocytose) and destroy microbes, together with natural killer cells and macrophages.
(D) Cytokine barriers — this matches (I) Interferons. Interferons are proteins released by virus-infected cells. They protect the healthy cells around them from further viral infection.
Note: A similar question was also asked in CUET (UG) 2026 on 29-05-2026 (Slot 2), and in CUET (UG) 2023 on 30-05-2023 (Slot 1).
NCERT Extract:
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. (ii) Physiological barriers : Acid in the stomach, saliva in the mouth, tears from eyes–all prevent microbial growth. (iii) Cellular barriers : Certain types of leukocytes (WBC) of our body like polymorpho-nuclear leukocytes (PMNL-neutrophils) and monocytes and natural killer (type of lymphocytes) in the blood as well as macrophages in tissues can phagocytose and destroy microbes. (iv) Cytokine barriers : Virus-infected cells secrete proteins called interferons which protect non-infected cells from further viral infection.”