Read the passage and answer the question given below.
When a host is exposed to antigens, which may be in the form of living or dead microbes or other proteins, antibodies are produced in the host body. This type of immunity is called active immunity. Active immunity is slow and takes time to give its full effective response. Injecting the microbes deliberately during immunisation or infectious organisms gaining access into body during natural infection induce active immunity. When antibodies are directly given to protect the body against foreign agents, it is called passive immunity.
Match List I with List II:
| List I | List II |
|---|---|
| A. Physical Barrier | I. Saliva |
| B. Cellular Barrier | II. Interferons |
| C. Physiological Barrier | III. Skin |
| D. Cytokine Barrier | IV. Polymorpho-nuclear leukocytes |
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-I, D-II
(A) Physical Barrier — this matches (III) Skin. The skin is the main barrier that stops microbes from entering.
(B) Cellular Barrier — this matches (IV) Polymorpho-nuclear leukocytes. Neutrophils (PMNL), monocytes and natural killer cells destroy microbes.
(C) Physiological Barrier — this matches (I) Saliva. Saliva, stomach acid and tears prevent microbial growth.
(D) Cytokine Barrier — this matches (II) Interferons. Virus-infected cells secrete interferons, which protect non-infected cells from further viral infection.
Note: The passage is taken from NCERT. NTA has put lines of the NCERT text together to make it. Most CUET (UG) questions come straight from NCERT, so study the book line by line, including figures and their titles.