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Section 1 Infectious Disease Chapter 5 Fighting Disease
Section 1 Infectious Disease
Chapter 5 Fighting Disease
Understanding Infectious Disease
When you have an infectious disease, pathogens have gotten inside your body and caused harm.
Pathogen: Organisms that cause disease.
Infectious Disease: Disease caused by the presence of a living thing within the body.
Understanding Infectious Disease
Famous People 1860’s – 1880’s
Joseph Lister: British Surgeon hypothesized that microorganisms caused infections. (washed his hands and equipment, what a brilliant man) Louis Pasteur: Showed that microorganisms cause certain kinds of diseases. Killing microorganisms can prevent disease.
Robert Koch: demonstrated that each infectious disease is caused by a specific kind of pathogen.
Kinds of Pathogens
There are 4 major groups of human pathogens.
BacteriaVirusesFungiProtists
Kinds of Pathogens
Bacteria: one-celled microorganisms, damage Body cells directly, and indirectly through toxins.
Toxin: Poison, that attacks kills or damages cells.
Kinds of Pathogens
Kinds of Pathogens
Viruses: tiny particles, much smaller than bacteria. Cannot reproduce unless they are inside a living cell.
Colds and Flu are caused by viruses.
Over 200 kinds.
Meds don’t work, body must kill with immune system.
Kinds of Pathogens
Kinds of Pathogens
Fungi:
molds and yeast
grows in warm, dark, and moist areas.
Examples: athlete’s foot and ringworm.
Kinds of Pathogens
Kinds of Pathogens
Protists: eukaryotic organisms unicellular, and multicellular organisms, such as the protozoans, slime molds, brown algae, and red algae.
Examples:
MalariaAfrican Sleeping SicknessAmebic Dysentery
Kinds of Pathogens
How Pathogens Are Spread
Pathogens can spread through contact with:
Infected personSoilFoodWaterContaminated objectInfected animal
Section 2 The Body’s Defenses
Chapter 5 Fighting Disease
Barriers That Keep Pathogens Out
First line of Defense:
Surfaces of SkinBreathing PassagesMouthStomach
These barriers trap and kill most all pathogensthat try to enter the body.
Barriers That Keep Pathogens Out
Skin:
Chemicals in oil and sweatFall off with dead skinTightly lined skin cells
Normally enters through skin cuts
Skin
Barriers That Keep Pathogens Out
Breathing Passages:
Contain mucus and ciliaSneeze and Cough
Breathing Passages
Barriers That Keep Pathogens Out
Mouth & Stomach:
Saliva contains destructive chemicals
Acid in stomach
Mouth & Stomach
Stomach
The Inflammatory Response
In the inflammatory response, fluid and white blood cells leak from blood vessels into nearby tissues. The white blood cells then fight the pathogens.
The Inflammatory Response
White Blood Cells
Phagocyte: white blood cell that engulfs pathogens and destroys them by breaking them down.
White Blood Cell
White Blood Cell
The Inflammatory Response
Inflammation
Blood vessels widenBigger area faster responseExtra fluid, creates a swollen area
The Inflammatory Response
Fever
Chemicals produce feverIncreased temp restricts infections ability to spread reproduce & grow.
Fever
The Immune System
The cells of the immune system can distinguish between different kinds ofpathogens. The immune system cellsReact to each kind of pathogen with adefense targeted specifically at that pathogen.
Immune System
The Immune System
T Cell
To identify pathogens and distinguish one kind of pathogen form another.
T Cell
The Immune System
B Cell
Produces proteins that help destroy pathogens.
Antibodies: are made for specific antigens, marks them for death.
B Cell
AIDS
Disease caused by the virus, HIV.
HIV is the only kind of virus known to attack the human immune system directly and destroy T cells.
AIDS
Section 3 Preventing Infectious Disease
Chapter 5 Fighting Disease
Active ImmunityImmunity: The body’s ability to Destroy pathogens before they can cause disease.
Active ImmunityActive Immunity: Your own immune system produces antibodies in response to the presence of a pathogen.
Active ImmunityThe Immune Response
T cells and B cells keep the “memory” of how to destroy pathogens that have all ready entered the body.
This response can last for life.
Active ImmunityVaccination
The process by which harmless antigens are deliberately introduced into a person’s body to produce active immunity.
Vaccine: consists of pathogens that have been weakened or killed but can still trigger the immune system.
Vaccination
Active ImmunityWhen You Do Get Sick
Antibiotic: chemical that kills bacteria or slows their growth with out harming body cells.
Nothing you can take for a viral infection.
Antibiotic
Passive ImmunityPassive Immunity
A person acquires passive immunity when the antibodies that fight the pathogen come from a source other than the person’s body.
Section 4 Noninfectious Disease
Chapter 5 Fighting Disease
Noninfectious DiseaseDiseases that are not caused by pathogens in the body.
Can not be transmitted from person to person.
AllergiesAn allergy develops in response to various foreign substances that set off a series of reactions in the body.
Allergens: A substance that causes an allergy.
Histamine: a chemical that is responsible For the symptoms of an allergy, such as Sneezing and watery eyes.
Allergy
Allergy
Allergens
Histamine
AllergiesAsthma:
A disorder in which the respiratory passages narrow significantly.
Can be brought on by stress and exercise.
Asthma
DiabetesHigh levels of glucose in the blood and may even excrete glucose in the urine. The person’s body cells, however, do not have enough glucose.
Insulin: enables body cell to take in glucose from the blood and use it for energy.
Glucose
Insulin
Insulin
Effect of DiabetesShort-Term Effects:
Weight lossFeeling weakHungry all the timeFeeling thirsty
Long-term Effects:BlindnessKidney FailureHeart Disease
Forms of DiabetesType I
Begins in childhood or early adulthood
Pancreas produces little or no insulinType II
Develops during adulthoodPancreas does not make enough
insulin, or body cells do not respond normally to insulin
Control through proper diet, and exercise.
Type I Diabetes
Type II Diabetes
CancerA disease in which cells multiply uncontrollably, over and over, destroying healthy tissue in the process.
CancerHow Cancer Develops
Tumors: Cells dividing out of control, not all tumors are cancerous. Cancer cells break off and destroy healthy tissue.
Blood and Lymph vessels can carry cancer cells around the body for new tumors to form.
Tumors
CancerCauses of Cancer
Tumors: Cells dividing out of control, not all tumors are cancerous. Cancer cells break off and destroy healthy tissue.
Blood and Lymph vessels can carry cancer cells around the body for new tumors to form.
CancerCancer Treatment
Surgery: Removal
Drugs: Use of chemicals to destroy cancer cells.
Radiation: High-energy waves to kill cancer cells, in specific spots.
CancerCancer Prevention
Avoid Carcinogens
Low-Fat Diet
Regular Checkups… Catch it early
Section 5 Cancer and the Environment
Chapter 5 Fighting Disease
Linking Cancer to the Environment
First Studies
1700’sChimney SweepsSkin Cancer
Linking Cancer to the Environment
A Link Between Soot and Cancer
Percivall PottCarcinogens in sootSame stuff in in the tar of
cigarette smoke
Linking Cancer to the Environment
Carcinogens in the Environment
The environment many contain carcinogens. To reduce the risk of cancer, carcinogens need to be removed or people need to be protected from them. (EPA)
Environmental Carcinogens Today
Ultraviolet Light
Skin CancerOzone going away
Environmental Carcinogens Today
Vinyl Chloride
Colorless gasPVC – plastic products
pipes, coating for wires, packaging, upholstery,
house wares, car parts.
Liver, brain, lung cancer
Environmental Carcinogens Today
Arsenic
Naturally Occurs in soil and rock
Wood Preservative (CCA) pressure treat
Liver, Bladder, Kidney, and Lung cancer
