a. Coverings of the body act as a habitat for many useful bacteria. The genus that enter the body need to compete with such useful bacteria for shelter and nutrients. A great number of germs get destroyed in this competition.
b. The rise in the body temperature reduces the rise of multiplication of pathogens, increases the effect of phagocytosis.
c. Antibodies destroy the pathogens in three different ways.
1. Destroy the bacteria by disintegrating their cell membrane.
2. Neutralise the toxin of the antigens.
3. Destroy the pathogens by stimulating other white blood cells.
d. Vaccines are the substances used for artificial immunization. Vaccines act as antigens that stimulate the defense mechanism of the body. Antibodies are formed in the body against them. These antibodies are retained in the body which in future protect the body from the pathogen responsible for the same disease.
