Question

How does the human body protect itself from infections?

Answer 1

The microorganisms are responsible for causing infections in the human body. There are various mechanisms which help the human body to protect and fight against these infectious agents. There are skin cells which forms the first line of defense and prevents the entry of pathogens. There are mucus-secreting cells, cells with cilia and acid production in certain regions which provide protection. There are immune cells which include the different types of lymphocytes. The B-cell and T-cells are considered the most important cells. The T-cells recognize the specific antigens and stimulate the B-cells and memory T-cells. The B-cells are responsible for the production of antibodies and the memory T-cells memorize the type of antigen and the antibody produced. The memory cells activate the B-cells to produce the same antibody on the second encounter of the same pathogen. There are other cells like the killer T-cells, neutrophils, macrophages and monocytes which phagocytose the foreign particles. These cells and structures provide protection to the human body against the pathogenic organisms.