Immune System Body’s way to maintain homeostasis (balance)

Pathogens- anything that causes illness in our bodies Enter the body through many ways Enter the body through many ways The pathogens that cause the most common illnesses are bacteria and virus The pathogens that cause the most common illnesses are bacteria and virus

Bacteria Are small living cells Are small living cells Cause illnesses by damaging cells and produce toxins Cause illnesses by damaging cells and produce toxins We need some bacteria to keep us healthy (in the digestive tract) We need some bacteria to keep us healthy (in the digestive tract)

BACTERIA Staphylococcus aureus Syphilis Streptococcus

Viruses Are NOT CELLS!!!! Are NOT CELLS!!!! They are DNA with a protein shell They are DNA with a protein shell Very, very small Very, very small Damage your cells by injecting their DNA into your cells…This causes your cells to explode Damage your cells by injecting their DNA into your cells…This causes your cells to explode

VIRUS Influenza HIV

Other Pathogens

FUNGI Athlete’s Foot Ringworm

PARASITE/PROTOZOAN Tapeworm Malaria

1 st line of defense The skin The skin “you are not getting past me” “you are not getting past me” Also sweat, tears, saliva, membrane linings, mucus stomach, urine (body fluids) Also sweat, tears, saliva, membrane linings, mucus stomach, urine (body fluids)

Skin Skin Protective envelop for the body Protective envelop for the body Bodily fluids Bodily fluids Chemicals in the fluids kill bacteria Chemicals in the fluids kill bacteria Helps flush the bacteria away Helps flush the bacteria away Mucus Mucus Traps the pathogens which then can be removed from the body Traps the pathogens which then can be removed from the body

Lab # “Snot” S- How does mucus work to protect your body? S- How does mucus work to protect your body? P- P- I-Materials: I-Materials: Gelatin, water, corn syrup, spoon and dust Gelatin, water, corn syrup, spoon and dust Instructions: Instructions: Add 50 ml hot water to gelatin Add 50 ml hot water to gelatin Add 50 ml of corn syrup Add 50 ml of corn syrup Mix Mix Add substances Add substances

C- C- Description of what happens Liquid Dust Large Particles

E- Evaluate E- Evaluate Describe what you did in this lab activity (2 sentences). Describe what you did in this lab activity (2 sentences). Describe how is mucus helpful in protecting your body? Describe how is mucus helpful in protecting your body?

2 nd line of defense Inflammatory Response Inflammatory Response When pathogens make it through the first line of defense your body responds by trying to get rid of the pathogen When pathogens make it through the first line of defense your body responds by trying to get rid of the pathogen

Signs of inflammatory response Swelling, redness, warmth and pain Swelling, redness, warmth and pain

What is actually happening The body sends out signals to cells- WHITE BLOOD CELLS (phagocytes) The body sends out signals to cells- WHITE BLOOD CELLS (phagocytes) Neutrophils Neutrophils Macrophages Macrophages Attack and eat the pathogen causes pus Attack and eat the pathogen causes pus

3 rd line of defense The immune system- gets awakened The immune system- gets awakened Recognizes, attacks, destroys and remembers the pathogen Recognizes, attacks, destroys and remembers the pathogen

The players… Memory cells remember the pathogen Memory cells remember the pathogen Antibodies are made to attack the pathogen Antibodies are made to attack the pathogen They attach to the pathogen and inactivate it They attach to the pathogen and inactivate it Antigens are possible pathogens Antigens are possible pathogens

Active immunity or Natural immunity Active immunity comes from first hand experience with the disease Active immunity comes from first hand experience with the disease Produces antibodies or T-Cells Produces antibodies or T-Cells Get sick or vaccine Get sick or vaccine

Passive immunity Get it from someone else like the mother to the baby Get it from someone else like the mother to the baby

Vaccines and immunizations Prevent your body from getting sick. Prevent your body from getting sick. Involves injecting dead pathogens into your body. Involves injecting dead pathogens into your body. Your body responds to attack them Your body responds to attack them They can not harm you because they dead but your body does not know that. They can not harm you because they dead but your body does not know that. Your memory cells will remember these cells so that if you get the pathogen for real your body will respond Your memory cells will remember these cells so that if you get the pathogen for real your body will respond

Spread of diseases How do diseases get spread? How do diseases get spread? Some through air, contact, and bodily fluids Some through air, contact, and bodily fluids Each disease is a little different Each disease is a little different

Spread of disease Mini-Lab: One person in the room will be “infected” with a disease. You will exchange fluid with three people. This exercise will show how easy it is for a disease to spread among populations. Mini-Lab: One person in the room will be “infected” with a disease. You will exchange fluid with three people. This exercise will show how easy it is for a disease to spread among populations. S- How easy is it for a disease to spread? S- How easy is it for a disease to spread? P-(How many people do you think will be infected?) P-(How many people do you think will be infected?)

I- I- Materials: test tube, solution, pipette, indicator Materials: test tube, solution, pipette, indicator Procedures: You will exchange fluid with 3 people in the classroom record who you exchanged with Procedures: You will exchange fluid with 3 people in the classroom record who you exchanged with C- C- Infected start: 1 Infected start: 1 Fluid Exchange 1______________ Fluid Exchange 1______________ Fluid Exchange 2______________ Fluid Exchange 2______________ Fluid Exchange 3______________ Fluid Exchange 3______________ Your status_____________ Your status_____________ Infected end:____________ Infected end:____________

E- E- Describe what happened to the number of people infected? Describe what happened to the number of people infected? How easily is it for some of the diseases to be transmitted? How easily is it for some of the diseases to be transmitted? Why is it important to use protection when engaging in sex? Why is it important to use protection when engaging in sex?

HIV/AIDS AIDS is caused by the Human Immunodeficiency Virus AIDS is caused by the Human Immunodeficiency Virus 30 million people have been infected 30 million people have been infected There is no vaccine There is no vaccine There is no known cure There is no known cure

HIV Is a virus that injects its DNA into healthy host (human) cells Is a virus that injects its DNA into healthy host (human) cells HIV can remain dormant for many years HIV can remain dormant for many years HIV targets cells responsible for killing pathogens (T-Cells) HIV targets cells responsible for killing pathogens (T-Cells) Develops into AIDS- body can not defend itself against pathogens Develops into AIDS- body can not defend itself against pathogens

Allergies Allergies are over reactions by the immune system to harmless antigens or substances Allergies are over reactions by the immune system to harmless antigens or substances

Hayfever- reacts to the pollen, creates increase in mucus and histamines Hayfever- reacts to the pollen, creates increase in mucus and histamines Asthma- causes swelling of the bronchioles Asthma- causes swelling of the bronchioles