Hint: The immune system is a network of biological processes that protects an organism from various diseases. Two types of immunity innate and acquired.
Complete answer: The immune system protects its host from infection with layered defenses of increasing specificity present in the body. Physical barriers prevent pathogens such as bacteria and viruses from entering the organism body. If a pathogen breaches these barriers, the innate immune system provides an immediate, but non-specific response to protect the body from them. Innate immune systems are found in all animals from birth. If pathogens successfully evade the innate response, vertebrates possess a second layer of protection, the adaptive immune system, which is activated by the innate response and it is stronger than innate immunity. Here, the immune system adapts its response during an infection to improve its recognition of the pathogen and this improved response is then retained after the pathogen has been eliminated, in the form of an immunological memory, and allows the adaptive immune system to mount faster and stronger attacks each time this pathogen is encountered.
The cells of innate immunity are neutrophils, macrophages, basophils, eosinophils and various blood cells. The cells of adaptive immune response are T- cells, mature in thymus and B- cells mature in bone marrow.
Signs of weak immune system are as follows- • Your Stress Level is very high • You Always Have a Cold, due to loss of fighting capacity against pathogens • You Have Lots of Tummy Troubles like diarrhoea, gas, constipation etc • Your Wounds Are Slow to Heal and may be painful • You Have Frequent Infections and produce harmful effects • You Feel Tired All the Time i.e prolonged weakness
Note: Various ways to boost immune system are- • Balanced diet • Exercise regularly • Have good sleep • Don’t smoke and drink • Don’t take much stress • Wash your hands and maintain hygiene