How does the body fight Diseases?
The body has several layers of defence mechanisms that work together to fight diseases caused by pathogens like bacteria and viruses. This complex and highly orchestrated response is known as the immune system, which involves various cells, tissues, organs, and molecules. Here's an overview of how the body fights diseases:
1.Physical Barriers:
The first line of defence is the body's physical barriers, which prevent pathogens from entering the body. These include:
- Skin: The outermost layer of the skin acts as a protective barrier against pathogens.
- Mucous Membranes: Line the respiratory, digestive, and urogenital tracts, trapping and removing pathogens.
2.Innate Immune Response:
When pathogens breach physical barriers, the innate immune response comes into play. This immediate and non-specific defence mechanism includes:
- Phagocytosis: Specialized cells called phagocytes engulf and digest foreign particles, including bacteria and damaged cells.
-Inflammation: When tissues are damaged, inflammation occurs. It leads to increased blood flow, bringing immune cells and nutrients to the affected area.
- Natural Killer (NK) Cells: These cells can recognize and destroy infected or cancerous cells.
3.Adaptive Immune Response:
The adaptive immune response is slower to develop but highly specific and long-lasting. It involves the activation of:
- B Cells: Produce antibodies that bind to and neutralize specific pathogens, marking them for destruction.
- T Cells: There are several types of T cells, including cytotoxic T cells that directly kill infected cells and helper T cells that assist B cells in producing antibodies.
- Memory Cells: After an infection, memory B cells and memory T cells are formed. These cells "remember" the pathogen and can quickly mount an immune response if the same pathogen is encountered again.
4.Complement System:
The complement system is a group of proteins that work together to enhance the effectiveness of antibodies and phagocytes in destroying pathogens.
5.Fever:
Elevated body temperature (fever) can inhibit the growth of some pathogens and enhance the immune response.
6.Interferons:
These proteins are produced by the cells infected with viruses and help to prevent the spread of infection to neighbouring cells.
7. Gut Microbiota:
The trillions of bacteria that reside in the digestive tract play a crucial role in preventing infections and maintaining overall immune balance.
8. Vaccination:
Vaccines work by introducing weakened or killed forms of pathogens or their antigens into the body. This process stimulates the immune system to develop memory cells without causing severe disease, providing immunity against future infections.
It's important to note that the immune system can be compromised by factors such as ageing, malnutrition, stress, certain medications, and underlying medical conditions. Maintaining good overall health, practicing hygiene, and receiving appropriate vaccinations are crucial for supporting the immune system in its fight against diseases.