Human immune system

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Vaccination: An injection of a weakened strain of an infectious microbe (pathogen) that causes the body to undergo active immunity (produce antibodies).

Passive Immunity

This is immunity where antibodies are given to a person from the blood of another person or animal.

This immunity only lasts for a short period of time.

ex: Breastfeeding mothers pass antibodies to their children through the milk.

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Autoimmune Disease

Autoimmune diseases are diseases where the immune system begins to attack itself.

Ex:

Rheumatoid Arthritis – crippling disease of the joints.

Lupus – disease of blood and organs.

Multiple Sclerosis – disease of nervous system

Cause(s): unknown

Cures/Treatments: No known cures. Usually treated with drugs.

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Allergies

Allergy

- An exaggerated response by the immune system to an allergen.

Allergen: a normally harmless substance that causes an allergic reaction.

ex: dust, pollen, mould, food, insect stings

Types of Allergic reactions

There are two types of allergic reactions.

a. Immediate – occurs within seconds and normally lasts for about 30 mins.

b. Delayed – takes longer to react and can last for a much longer time.

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What happens during an allergic reaction?

During an allergic reaction antibodies cause histamines to be released from certain cells.

Histamines cause:

a. Swelling of tissues

b. Release of fluids (runny noses and eyes)

c. muscle spasms (some cases)

Anaphylaxis or anaphylactic shock:

This is the sudden and severe allergic reaction to a substance that can cause death.

Treatments for Allergies

Avoidance of material – especially food.

Epinephrine – “epi – pen”

Antihistamines -- benadryl

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Homework

Complete STSE – “What is Cancer?” (Scriptum)

Complete Q’s 1,2,4,6,7 on page 386 MHR