Sample Nutrition Coursework Paper on Function of Immune System on a Cellular Level to Fight the Flu Virus

Function of Immune System on a Cellular Level to Fight the Flu Virus

The immune system is a balanced network of cells and organs that work together in host bodies defending them against diseases. The immune system works to stop threats like viruses and bacteria from getting into the host’s body causing infections and diseases. It defends the body from any disease-causing microorganisms like the flu virus. After detecting any foreign substances invading the body, for instance, flu virus, it sends immune cells that destroy and get rid of all the flu viruses protecting living organism from suffering the flu raising the cellular level in the host’s body (Iwasaki and Medzhitov 293).

Once the immune system detects flu virus, it counters them by stimulating specialized cells that destroy the invaders in host’s body. Flu virus like any other virus cannot survive alone and hence must be in the host’s body where they migrate to replicate and multiply in numbers. The immune system causes the activation of white blood cells called lymphocytes that have two common branches known as T cells and B cells. These cells multiply in numbers to counter the flu virus raising the cellular level. B cells after detecting flu virus make protein antibodies that label the virus as a foreign substance for other cells to destroy it. B cells divide in the body after detecting flu virus producing many plasma cells that secrete a large number of antibodies, which fight the flu virus. T-cells work to clear out body infections against flu virus through recognizing infected body cells and hence destroying them. B and T’s cells do not persist in the blood after they attack and destroy flu viruses. The immune system hence responds by lowering the cellular level after infection (Janeway et al., 39).

Only small numbers of B and T cells persist in the immune system and in the blood after the infections. These are meant to keep the memory of the flu virus and would help the immune system respond activating them to destroy flu virus faster anytime they enter the body. The Immune system responds by deactivating the white blood cells lowering their levels in the host’s body after fighting flu virus thus lowering the cellular level (Janeway et al. 55).


Works Cited

Iwasaki, Akiko, and Ruslan Medzhitov. “Regulation of adaptive immunity by the innate immune system.” science 327.5963 (2010): 291-295.

Janeway, Charles A., et al. Immunobiology: the immune system in health and disease. Vol. 2. London: Churchill Livingstone, 2011.