Question

Which of the following is an example of active acquired immunity?
A. The nursing mother transfers some antibodies to the infant through colostrum (breast milk).
B. The person recovered from measles does not get measles again.
C. Injection of anti-tetanus is given after injury.
D. We do not suffer from distemper, a fatal canine disease.

Answer 1

Hint: Active acquired immunity is the kind of immunity that is gained after birth when a person is exposed to antigens, and the antibodies are produced in its response. Moreover, these antibodies save a person from future encounters with the disease-causing organism.

Complete answer: -The first statement given to us is that the nursing mother transfers some antibodies to the infant through colostrum (breast milk): This is a type of natural passive acquired immunity. Acquired immunity is the kind of immunity that we gain after birth from various external sources and it is pathogen-specific. In passive immunity, the readymade antibodies are directly administered into the body to protect it from diseases. Since the colostrum is natural, therefore, it is natural passive immunity.
-The second statement given to us is that the person recovered from measles does not get measles again: This is a type of natural active acquired immunity. Acquired immunity is the kind of immunity that we gain after birth from various external sources and it is pathogen-specific. In active immunity when a person is exposed to antigens, then antibodies are produced in its response. These antibodies are then saved as a memory to prevent the attack in the future.
-The third statement given to us is that the injection of anti-tetanus is given after injury: It is a type of passive immunization and second-generation vaccination. In passive immunity, the readymade or preformed antibodies are directly administered into the body to protect it from diseases. In this case, the antibodies need to be administered immediately, and every time after the exposure.
-The fourth statement given to us is that we do not suffer from distemper, a fatal canine disease: It is a type of artificial active acquired immunity. This is because when humans are vaccinated for measles, then they get natural antibodies for distemper too.
Thus, based on the above information we can conclude that the statement that a person recovered from measles does not get measles again is an example of active acquired immunity.
Hence, the correct answer is option (B).

Note: Immunity is defined as the overall ability of an organism to fight with the disease-causing organisms. Immunity is of two types. These two types are as follows –
Innate immunity – It is the kind of immunity that is present at the time of birth. Due to this reason, it is also known as inborn immunity.
Acquired immunity