Match the Column I with Column II :
| Column I | Column II |
| A. Active natural immunity | 1. Antibodies transferred through the placenta |
| B. First line of defense | 2. Complement proteins and interferons |
| C. Passive natural immunity | 3. Direct contact with the pathogens that have entered inside the body |
| D. Second line of defense | 4. Surface barriers |
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) – A-3,B-4,C-1,D-2
| Column I | Column II |
| A. Active natural immunity | 3. Direct contact with the pathogens that have entered inside the body |
| B. First line of defense | 4. Surface barriers |
| C. Passive natural immunity | 1. Antibodies transferred through the placenta |
| D. Second line of defense | 2. Complement proteins and interferons |
A. Active natural immunity → 3. Direct contact with the pathogens that have entered inside the body
- Explanation: Active natural immunity occurs when the body is exposed to a pathogen, and the immune system responds by producing its own antibodies. This type of immunity is acquired naturally through infection and leads to long-term protection.
B. First line of defense → 4. Surface barriers
- Explanation: The first line of defense refers to the body's initial barrier to prevent pathogens from entering. This includes physical barriers like the skin and mucous membranes.
C. Passive natural immunity → 1. Antibodies transferred through the placenta
- Explanation: Passive natural immunity occurs when a person receives antibodies from another source rather than producing them. In natural cases, this often happens during pregnancy, where a mother transfers antibodies to her baby through the placenta, providing immunity.
D. Second line of defense → 2. Complement proteins and interferons
- Explanation: The second line of defense comes into play if pathogens bypass the first line. This includes the internal defenses of the body, such as phagocytes, natural killer cells, inflammation, and the action of complement proteins and interferons, which help fight infections within the body.