Question

The injection of serum of horse which has been repeatedly injected by cobra venom into a person bitten by cobra results in
A. No immunity
B. Natural immunity
C. Active immunity
D. Passive immunity

Answer 1

The cobra venom acts as an antigen for activating immunity response in the horse. The serum from the horse is transferred to another person for cobra bite.

Step by step answer: The injection of serum of horse which has been repeatedly injected by cobra venom into a person bitten by cobra results in passive immunity.
Immunity:- It refers to protection against disease. It involves the generation of response against the foreign organism or substances this response is called the immune response. It is a control and coordinated response. The cells, organs, and molecules involved in the immune response from the immune system. Immunity can be innate or adaptive ( active and passive).
Natural immunity: It is also called innate immunity, it is the first line of defense. It is present from birth and it is nonspecific, as it acts against all pathogens. This response involves barriers like physical(skin), chemical(lysozymes in eyes), and inflammatory. It has a fast response but no memory i.e. on subsequent reactions with the same pathogen response remain the same.
Active immunity: It is an adaptive response, in this type of immunity the organism develops its natural response against the antigen i.e. activation of the immune response. It can take a longer time. But once developed, it produces memory cells. These memory cells hasten the subsequent immune response.
Passive immunity: Passive immunity results from transfer antibodies or immune cells from immune to a non-immune organism.
Additional information: The vaccination involves the activation of the immune response induced by the attenuated or heat-killed pathogen.

Note: Serum of horse injected by cobra venom-induced active immunity in the horse, transfer of this serum containing antibodies into the person with cobra bite induced passive immunity in the person.