Zoology MCQs for NEET — Practice Questions with Answers

The NCERT explains, 'The vaccines also generate memory – B and T-cells that recognise the pathogen quickly on subsequent exposure and overwhelm the invaders with a massive production of antibodies.' These memory cells are key for long-term immunity.

The NCERT states: 'If a person is infected with some deadly microbes to which quick immune response is required as in tetanus, we need to directly inject the preformed antibodies, or antitoxin... Even in cases of snakebites... contain preformed antibodies... This type of immunisation is called passive immunisation.'

The NCERT mentions: 'A large number of other infectious diseases like polio, diphtheria, pneumonia and tetanus have been controlled to a large extent by the use of vaccines.' Pneumonia is listed among these.

The NCERT states: 'Recombinant DNA technology has allowed the production of antigenic polypeptides of pathogen in bacteria or yeast. Vaccines produced using this approach allow large scale production and hence greater availability for immunisation, e.g., hepatitis B vaccine produced from yeast.'

The NCERT explicitly provides an example: 'e.g., hepatitis B vaccine produced from yeast' as a vaccine developed using recombinant DNA technology.

The NCERT highlights: 'Vaccines produced using this approach allow large scale production and hence greater availability for immunisation...'

The NCERT defines active immunity: 'When a host is exposed to antigens... 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... induce active immunity.'

Passive immunity involves receiving pre-formed antibodies (mother's milk, placental transfer, antitoxins, anti-venom). Vaccination against polio stimulates the body's own immune system to produce antibodies, which is active immunity.

The NCERT states: 'The yellowish fluid colostrum secreted by mother during the initial days of lactation has abundant antibodies (IgA) to protect the infant.' This is an example of passive immunity.

The NCERT lists: 'Awareness about diseases and their effect on different bodily functions, vaccination (immunisation) against infectious diseases, proper disposal of wastes, control of vectors and maintenance of hygiene in food and water resources are necessary for achieving good health.' Vaccination is directly mentioned as part of maintaining good health and disease awareness.