Many physiological activities in the body prevent the entry of the germs into the body.
Some of them are as follows:
- Fever: The invading germs secrete different types of toxins. As a result, the number of WBC is increased to destroy them. In addition, macrophages are also increased which secrete pyrogens. These pyrogens increase body temperature which inhibits bacterial growth.
- Lysozyme: The body secretions such as tears, saliva, sweat etc. are increased as a result of infection. These secretions contain an enzyme lysozyme which kills the
germs by digesting their cell wall.
- The stomach secretes dilute HCl which makes the pH strongly acidic (pH 1 to 2). It acts as a strong germicidal.
- There is the release of bile juice into the duodenum which also acts as germicidal.
- The mucus secreted in the respiratory passage acts as a barrier for germs.
- The cerumin found in the sebum secreted by the sebaceous glands of the skin also kills germs.
