Immune System - are organs, tissue, and cells that works together to prevent illnesses

The Immune System includes:

• White blood cells
• Lymph nodes
• Tonsils
• Thymus gland – makes T-cells (lymphocytes)
• Bone marrow – makes B-cells
• Spleen – filters blood and destroys bacteria

Disease - is any change that disrupts the normal functioning of the body

Examples of Pathogens:

• Virus (EX: varicella, herpes)

• Bacteria (EX: E. coli, tetanus)

• Fungi (EX: athlete’s foot)

• Parasites (EX: worms, lice)

How the Immune System Works

• Human bodies have 3 lines of defense
• 1st line - barriers
• 2nd line – inflammatory response
• 3rd line – immune response

1st Line - Barriers

• Skin keeps things out
• Chemicals like sweat and tears are neutralized pathogens
• Mucus & cilia – traps pathogens

2nd Line - Inflammatory Response

• Macro phage devours germ
• Inflammation
• Fever

3rd Line - Immune Response

• Specific immune response (body responds to a specific pathogen/antigen)
• Has antigens

Macrophage - devour invaders and launch the immune system attack

Helper T Cells - coordinate immune system attacks by activating other immune system cells

Antibodies - attaches themselves to the foreign substance

B Cells - tag invaders with antibodies so that other immune system cells will know that they have to destroy them

Antigens - are a substance made by pathogens that cause harm and are exposed to identify the invader

Killer T Cells - devour invaders or release toxic chemicals that kill invaders

Memory Cells - make immune responses faster when the next time an invader comes around

Types of Immunity

• Passive immunity – immunity that is temporary, it was transferred from another person
(EX: Mother to newborn)
• Active immunity – immunity resulting from exposure to a pathogen
(EX: vaccinations)

HIV - human immunodeficiency virus

Immune Response to the HIV

• Attacks helper T cells
• Results in B and Killer T not coming which also results to the virus unchecked

AIDS - acquired immune deficiency syndrome

A Person Has Aids When:

• He/she has HIV
• Has a CD4 cell count
• has any opportunistic illnesses

Opportunistic Illnesses- are any illness that a person has because they have no immunity

	Created by irenepapers over 9 years ago

Immune System Quiz Notes (7th Grade) by Irene Kim To: Sarah Chowdhury