The Immune System

Nicole PetryGabrielle Henderson

Marquis Equan Dixon Ethan Chaparro

Functions of the Immune System

• made up of special cells, proteins, tissues, and organs, that defend people against germs and microorganisms

• Keeps people healthy and prevents infection• Problems lead to illness and infection• Attacks organisms that try to harm the body• cells involved are white blood cells, or

leukocytes

Two basic types of leukocytes

• Phagocytes- help the body chew up invading organisms• Lymphocytes- cells that allow the

body to remember and recognize previous invaders and help the body destroy them

Leukocytes are produced or stored in many locations in the body, including the thymus, spleen, bone marrow, and lymph nodes

• LET’S EXAMINE THE MENTIONED ORGANS

BONE MARROW

• Not exactly an organ• Lies inside most of our bones• Creates hematopoietic stem cells through the

process of hematopoietis• stem cells differentiate into all sorts of blood and

lymphatic cells - such as red blood cells, white blood cells, platelets

• Some cells mature in bone marrow and others travel to other areas to complete their nutrition

Bone Marrow

Spleen

• Filters the blood, destroying old or damaged blood vessels

• Contains specialized cells of the immune system that look for foreign particles as blood circulates

Spleen

Thymus

• Precursors from bone marrow(thymocytes) mature into T-cells

• T-cells are responsible for directing and making the immune system adapt to foreign antigens

• The thymus grows until puberty then starts to deteriorate after puberty

• Old people get sick faster and are more susceptible to cancer because of lack of a thymus

Thymus

Lymph Nodes

• Lymph nodes filter the lymph • Found in the throat, armpit, stomach, and

other places• Lymph is confused of fluids which drain from

tissues• Lymph nodes contain the same specialized

cells found in the spleen, which sample the incoming particles and respond accordingly

Lymph Nodes

What happens when it breaks down?

• If our immune system does not recognize the different antigens, its response for these antigens will cause use disease

• FOR EXAMPLE: If food isn’t recognized as harmless, the immune system will ‘overreact’ and will cause a hypersensitivity reaction and the person can be considered ‘allergic’.

HIV and the immune System

• HIV attacks T-cells created by the thymus• Because the thymus deteriorates with age,

your immune system gets worse• AIDS is caused by the HIV virus because T-cells

die

Bibliography• http://kidshealth.org/parent/general/body_ba

sics/immune.html• http://www.smartlivingnetwork.com/immunit

y-system/b/what-organs-make-up-your-immune-system/

• en.wikipedia.org/wiki/Thymus• Immunologyofpregnancy.com• www.sciencedaily.com/releases/

2008/02/080221183340.htm