Question

Read the following statements (A - D) and select the true (T) and false (F) ones regarding Acquired immunity

A. The formation of memory cells happens in the case of natural passive immunity

B. Anti-venom against snake bite is an example of natural active immunity

C. Attenuated pathogens are the example of vaccines that can provide immunity for a long time

D. Nasal- or Nasopharynx-Associated Lymphoid Tissue (NALT) represents the immune system of the nasal mucosa and is a part of Mucosa-Associated Lymphoid Tissue (MALT) in mammals

• A. A – T, B – T, C – F, D – T
• B. A – T, B – F, C – F, D - T
• C. A – F, B – F, C –T, D - T
• D. A – T, B – T, C – T, D – T

Answer 1

The correct option is C A – F, B – F, C –T, D - T

An individual, after their first instance of infection from a pathogen mounts a slow immune response. As their immune system develops, their body also produces B and T memory cells. These memory cells respond in a quick manner for subsequent infection of the same pathogen. This is natural active immunity.

Administration of preformed antibodies in the form of antisera (anti-rabies, anti-venom etc.) is an example of artificial passive immunity.

Vaccines are made up of either dead or alive but attenuated (artificially weakened) pathogens, memory-cells are formed; hence immunity persists for a long time.

Nasal- or nasopharynx-associated lymphoid tissue (NALT) is a small system of lymphoid tissues present in the various submucosal sites of the body. NALT represents immune system of nasal mucosa and is a part of mucosa-associated lymphoid tissue (MALT) in mammals. It protects body from airborne viruses and other infectious agents.