Passive immunity can be obtained by injecting
Some people who have suffered from a disease may not be affected again during their life time; such immunity is called
A malfunction of the lymph nodes would most likely interfere with the
Assertion : Interferons are effective against viruses.
Reason : Proteins which can be synthesized only by genetic engineering are effective against viruses.
In higher vertebrates, the immune system can distinguish selfcells and non-self. If this property is lost due to genetic abnormality and it attacks selfcells, then it leads to