Immune System

The Immune System

Our body has defenses that help us to fight off invading viruses and bactera. It is particularly useful when an illness is a cough, sneeze, handshake, or doorknob away.

Our bodies maintain three lines of defense: the skin, secretions of mucus/tears/sweat/saliva, and white blood cells.We are born with some disease fighting capabilities, these are called innate immunities.

First Line of Defense

This is a non specific defense. Meaning it does not target specific illnesses, but tries to stop all kinds, and is non responsive. this done with the integumentary system, the skin. The skin is a nonspecific defense because it wards off viruses and bacteria with out allowing them into our body. Now they can still find there way in through any of the openings on your face, or an open wound.Tears and saliva have a special enzyme that breaks down the cell wall of bacteria. the nose and throat have a mucus that helps catch pathogens(disease causing agents like bacteria or viruses). Sneezing and coughing help clear these unwanted pathogens from their respective airways. The bacteria either go out of the body or get swallowed into the acidic environment of the stomach.

The Second Line of Defense

If a pathogen makes it pas tthe first line, the second line of defense becomes active. It is also nonspecific despite that it is supported by white blood cells and inflammation. Inflammation is caused by white blood cells moving to the infected tissue and calling in for more white blood cells. Some white blood cells destroy pathogens by eating them, some release a histamine. A histamine is a chemical that helps destroy toxic agents released by the pathogen, and is the primary cause of the inflammation.

White blood cells can also release a chemical that causes the hypothalmus to elevate the body temperature, trying to make the environment unsuitable for the pathogen.

Vaccines and Antibiotics

Vaccines are shots that help give you an immunity to a virus

Antibiotics are usually pills that help you fight off bacterial infections

Immune and Integumentary

•The integumentary system is our skin and which is our body’s first line of defense.

•The integumentary system serves as a barrier against infection and injury. The skin blocks bacteria and virus from entering the body.

Immune and Respiratory

•If a pathogen gets past the first barrier the second barrier is activated

•Tears and saliva contain enzymes to help break down bacteria.

•When particles get into our respiratory tract through (nose and mouth), the nose and throat secrete mucus to trap the bacteria.

•Then when you cough and sneeze you will get rid of pathogens before they enter the lungs.

Immune and Lymphatic

•The lymphatic system is technically apart of the immune system, and a system of vessels that carry lymph fluid.

•The lymph fluid is able to recognize cells as healthy or unhealthy, based on protein markers called antigens found on the cell membrane.

–B lymph (b-cells) provides immunity against pathogens in blood

–T lymph (t-cells) provides immunity against pathogen within cells

Immune and Circulatory

•If a pathogen makes it past the initial barrier the second line of defense is activated causing an immune response.

•An immune response means the body begins making millions of white blood cells that travel in the blood to find, attack and destroy pathogens and infected cells.

•Some white blood cells actually consume and destroy cells, others activate the production of antibodies that identify bacteria and viruses to destroy them.