The immune system is a complex network of organs, cells and proteins that defends the body against infection, whilst protecting the body's own cells. This network first tries to keep out germs like bacteria, viruses, fungi, and parasites and then deals with them if they manage to get in. If it senses something in your body that could be bad for you, it triggers the release of special cells which attack and annihilate the intruder. The immune system keeps a record of every germ (microbe) it has ever defeated so it can recognise and destroy the microbe quickly if it enters the body again.
The main parts of the immune system are: 1/ White blood cells (WBC): search for, attack and destroy germs. Each WBC type has a specific mission and a different way of recognizing a problem, communicating with other cells on the defense team and performing their function. 2/ Lymph nodes: small glands filter and destroy germs. Lymph nodes contain immune cells that analyze invaders. They then activate, replicate and send specific WBCs to fight off that particular invader. You have hundreds of lymph nodes in your neck, armpits, and groin. Swollen, tender lymph nodes are a clue that your body is fighting an infection. 3/ Spleen: stores WBCs and filters blood, destroying old and damaged red blood cells. 4/ Tonsils & adenoids: in throat & nasal passage, trap microbes as soon as they enter your body. Their immune cells produce antibodies to protect you from throat and lung infections. 5/ Thymus: small organ helps mature a type of WBC to recognize and remember an invader so that an attack can be quickly mounted the next time it is encountered. 6/ Bone marrow: stem cells in the spongy center of your bones develop into red blood cells, plasma cells and a variety of WBCs and other types of immune cells. Your bone marrow makes billions of new blood cells every day and releases them into your bloodstream. 7/ Skin, mucous membranes et al.: skin prevents and destroys germs before they enter your body. Mucous membranes in the respiratory tracts secrete mucus which germs stick to before being eliminated. Enzymes found in sweat, tears, saliva and mucus membranes as well as secretions in the vagina all defend and destroy germs. 8/ Stomach and bowel: Stomach acid kills many bacteria when they enter your body. You also have good bacteria in your intestines that kill harmful bacteria.
Symptoms indicate what your immune system is doing to fight infection: 1. Runny Nose/Nasal Congestion— helps wash germs from the nose and sinuses. 2. Coughing and Sneezing—mucus traps offending microbes, which are expelled through coughing and sneezing. 3. Fever— viruses are sensitive to temperature changes and cannot survive above normal body temperature. 4. Muscle Aches and Pain—the immune system pulls protein from muscles, leaving your muscles achy. Vitamins and minerals that support immune function include:
vitamin A
vitamin D
vitamin E
iron
folic acid
zinc
(Adapted from: www.medicalnewstoday.com; www.webmd.com. Photo credit: www.drjockers.com)
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