Immune System

Protection against Pathogens Diseases are caused by microorganisms. Microorganism – tiny living things, many one celled Called Pathogens Read pages 562-566

Lines of Defense Body has 2 lines of defense First = keeps pathogens out Second = detects and destroys pathogens

First Line of Defense Skin = barrier between your body and the environment Keeps pathogens OUT Reading page 568

Sweat Glands EXCRETE salts that help kill bacteria on skin Tears wash pathogens out of eyes Also contain salt

Nose hair filters pathogens out of the air you inhale. Mucus and cilia trap also trap pathogens.

Stomach Acids kill pathogens that enter your body in food

Second Line of Defense White blood cells – fight pathogens that get through the first line Types of white blood cell s used in 2nd defense: Phagocytes – swallow and destroy pathogens Page 569

Third Line of Defense Attacks specific pathogens Involves phagocytes, T-Cells, and B-cells (types of white blood cell) Page 570

B-Cells: Make Antibodies T-Cells: ATTACK B-Cells: Make Antibodies Antibodies – proteins made by the body to kill a specific pathogen Page 571 figure 7

Immunity Immunity – bodies ability to protects itself from disease Two Types Active Passive 576 top paragraph

Active Immunity Active Immunity – Develops after exposure to a pathogen Immune system is prepared to respond when it sees the pathogen again Two ways: Get the disease Vaccine – small dose of weakened pathogen introduced to body 576-579

Passive Immunity Passive Immunity – Antibodies made by one organism are transferred to another organism Acquired: before birth, mother to baby Vaccines with Antibodies Rabies Page 580

Why might frequent hand washing help protect your from disease Why might frequent hand washing help protect your from disease? What are some other ways your could protect yourself and other people from disease?

Immune System: Lesson Review By which process can a person acquire active immunity to a disease? A. Injection with antibodies B. Treatment with antibiotics C. Vaccination D. Following Sanitary Procedures

Immune System: Lesson Review 2. Which substance is involved in both active immunity and passive immunity? A. Antibiotic B. Antibody C. Vaccine D. Mucus

Immune System: Lesson Review 3. How do phagocytes protect the body from disease? A. They produce white blood cells B. They engulf and kill pathogens C. They produce T and B cells D. They prevent pathogens from entering the body

Immune System: Lesson Review 4. Your mother is worried because she heard that the chickenpox vaccine your baby brother is going to receive is actually a weakened form of a viral disease. How do you explain to her that being injected with the disease will actually help protect your brother?

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