Download Three Lines of Defense Powerpoint

The Immune System
Fights for You PowerPoint
The story of how your immune systems protects
you from disease causing pathogens.
Total Slides: 40
Table of Contents
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Bad guys: pathogens
First line of defense: skin, mucous, sweat glands
Second line of defense: white blood cells
Good guys: proteins
Non-specific responses
Specific responses
• cellular immunity
• humoral immunity
• Bacteria:
•structure, types, reproduction, attack methods,
diseases, antibiotics
• Virus:
•structure, types, reproduction, attack methods,
diseases, vaccinations
Organs of the Immune System
The Bad Guys: PATHOGENS
1. Pathogens are disease causing agents.
2. Three types of pathogens are bacteria,
viruses, fungi, protozoa, parasites.
3. Bacteria cause illnesses by releasing
chemicals that are toxic to cells.
4. Viruses cause illnesses by injecting genetic
information into cell, causing it to react and
sometimes mutate.
A. The Immune System
• 1. Your immune system fights infections and
attacks invading pathogens such as bacteria
and viruses.
• 2. It has the first line of defense and the
second line of defense.
B. First Line of Defense:
Keeping Pathogens Out
• 1. Skin creates a physical barrier.
• 2. Mucous Membrane
(Mucus/Saliva/Tears) contains enzymes
that break down the cell walls of many
bacteria.
• 3. Sweat Glands creates an acidic
environment to kill bacteria.
First Line of Defense
Skin and Mucous Membrane
Second Line of Defense:
White Blood Cells
• A. White Blood Cells: Find and kill pathogens.
• The six types of white blood cells are:
a. basophil
b. mast cell
c. neutrophil
d. macrophages
e.*lymphocytes (T cells and B cells)
f. eosinophil.
The Good Guys: Proteins
• The immune system uses three types of
proteins to fight off pathogens:
• 1. complement proteins- cause pathogens to
burst.
• 2. antibodies- proteins made by B cells to
destroy pathogens.
• 3. interferons- produce enzymes to destroy
viruses.
C. Nonspecific and Specific
Responses
• 1. NONSPECIFIC RESPONSE
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a. Inflammation
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b. Fever
• 2. SPECIFIC RESPONSE
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a. Cellular immunity (T cells)
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b. Humoral immunity (B cells)
D. Non-Specific Response
• 1. Inflammation: Swelling, redness, pain,
itching, and increased warmth.
EX: You scrap your knees, a pathogen
enters your body, and your body responds
by making histamines and white blood
cells.
2. Fever: Your body’s temperature will
increase and cause white blood cells to
destroy pathogens.
E. SPECIFIC RESPONSE: CELLULAR
IMMUNITY
T cells destroy infected body cells.
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1. Phagocytes (specific cells) engulf pathogens (foreign
cells) and display the antigen (protein markers) on its
membrane.
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2. T-cell binds to antigen on membrane.
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3. T-cell divides and becomes memory T cells activated
T-cells.
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4. The activated T cell binds to infected body cells and
causes it to burst.
• F. SPECIFIC RESPONSE:
HUMORAL IMMUNITY
• B cells produce antibodies that destroy
pathogens.
• 1. Pathogens binds to antibody of inactive B cells.
• 2. T cell binds to antigen and activates B cells.
• 3. B cells divide and differentiates into memory B
cells and activated B cells.
• 4. Activated B cells produce antibodies that causes
pathogens to clump up together.
• 5. Phagocytes eat the pathogen clumps.
BACTERIA
A. Introduction
• 1. Bacteria belong to the kingdom
Monera/Prokarytoes.
• 2. Bacteria are simple single-celled organisms.
They do not have a nucleus. They do not have
membrane-bound organelles.
B. Bacteria have different shapes
• 1. Sphere (Cocci)
Ex. Staphylococcus aureus
cause skin infection
• 2. Spiral (Spirochete)
Ex. Leptospira
cause liver and kidney
infections
• 3. Rod (Bacilli)
Ex. Bacillus sutillis produce
antibiotics
C. Bacteria reproduce rapidly by AN
ASEXUAL REPRODUCTION process
called binary fission
Step 1: Bacteria duplicate DNA
Step 2: Bacteria split into two identical cells
Step 3: Each cell receives one molecule of DNA
and some cytoplasm.
(If you place a single bacteria into a culture dish
with lots of food, after six hours, there could be
476 million bacteria.)
D. How bacteria causes disease
• 1. Some bacteria are called pathogens
because they cause diseases.
• 2. Bacteria attacks the host’s (living organism)
cells WITHOUT entering the cell.
• 3. Bacteria releases toxins, poisonous
substances that destroy cells.
E. WAYS BACTERIA CAN SPREAD DISEASES
• 1. Water can carry pathogens.
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Ex. Cholera, a serious disease that causes diarrhea and
vomiting, is transmitted through polluted water.
• 2. Food can be contaminated by bacteria.
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Ex. Salmonella bacteria causes food poisoning.
• 3. Some bacteria are transmitted by air.
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Ex. Tuberculosis bacteria invades the lungs and causes
fatigue, cough, bleeding, and death.
• 4. Some bacteria are transmitted by insects (fleas, lice,
ticks)
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Ex. Lyme disease, first identified in 1975, is transmitted
by ticks and is common among pets, especially dogs!
Healthy Lung
Lung with Tuberculosis
The Bubonic Plague
From 1340-1400, an estimated 75 million people
died from Bubonic plague (aka Black Death) in
Europe and Asia. It is estimated to have wiped
out HALF of the European population. The Bubonic
Plague, transmitted by fleas from infected animals, causes
high fevers, swollen glands, muscle pain.
F. Controlling Bacterial Disease
We can prevent diseases caused by bacteria by
doing the following:
1. Sanitation
- clean conditions
-treating water with chemicals
2. High and low temperatures
- heating food (pasteurization)
- cooling food to a few degrees below zero.
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3. Antibiotics
a. Medicine, such as penicillin, kills
bacteria. Each antibiotic is only effective
against certain bacterial infections
b. Antibiotics kills bacteria without
destroying your cells.
The Story of Penicillin
Alexander Fleming, a physician, discovered penicillin by
accident! He found a blue-green mold growing on one of
his bacterial samples and got angry because his
experiment was contaminated. However, he noticed that
bacteria did not grow near the mold!!! He studied it and
found out that the mold released a chemical (penicillin)
that was poisonous to bacteria.
Serendipity!!! Eureka!!!
Penicillin is one of the most common medicine used today.
Thanks Dr. Fleming.
Virus
A. Definition
• 1. A virus is NOT a living thing.
• 2. Viruses are microscopic particles that
invade and often destroy the cells of plants,
animals, fungi, and bacteria.
Three Types of Viruses
B. Viruses are parasites
• 1. Viruses are small simple particles with a
core of genetic material (DNA or RNA)
surrounded by a protein coat.
• 2. Viruses become active when they are
inside living cells.
• 3. Viruses can only reproduce inside the host
cells.
C. How Virus Attacks Host Cells
• 1. A virus attaches to host cell.
• 2. The virus enters the cell, seizes control of it, and
transform it into a virus factory.
• 3. Virus uses cell to replicate genetic information
(either DNA or RNA) and make proteins.
• 4. New viruses are made.
• 5. Virus either break out of cell by budding through cell
membrane OR burst the cell membrane, killing the cell.
Virus infects and reproduces
D. Viruses can transmit diseases
• -Viruses can be transmitted by air, food and water
contamination, mosquitoes, and contaminated
blood or fluids.
• 1. Cold and Flu (Influenza)
(Cold and flu symptoms are similar except flu has more
symptoms such as fever, headache, aches, and pains)
• 2. AIDS caused by HIV (Human Immunodefiency
Virus)
• 3. Polio- causes respiratory problems and paralysis.
In 1921, Franklin D. Roosevelt was attacked by poliomyelitis
(aka polio) which paralyzed his legs. He became the 32nd
president in 1933!!!
• 4. Smallpox- fever, pustules on skin, fatal
• 5. Measles- rash, high fever, congestion in nose
and throat
-In the last 150 years, measles have killed
approximately 200 million people worldwide. In
1963, vaccines became available.
• 6. Yellow fever- nausea, fever, liver cell
destruction, fatal
-As of 2001, yellow fever causes 200,000 illnesses
and 30,000 deaths in unvaccinated populations.
• 7. Chicken pox- rash, fever
F. Treating Viral Infections with
Vaccinations
1. Vaccination is an effective defense against most viral
diseases.
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-Vaccines contain antigens that are made harmless
by chemicals or genetic engineering. When injected
into body, your immune system produces antibodies
to virus.
• 2. Vaccines are not effective against rapidly evolving
viruses.
• - Ex. The influenza virus and HIV virus
3. Antibiotics do NOT work against viral infections
because they work on bacteria not viruses.
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Vaccines are made from weakened
pathogens.
• A vaccine stimulates the body’s own immune response.
• Vaccines prepare the immune system for a future attack.
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Vaccines are the only way to control the spread of viral disease.
Vaccinations for Measles
The Story of Smallpox
Smallpox virus produced tiny postules or sores that developed
scabs and often turned into permanent scars. Smallpox killed half
of those who contracted it. When explorer Hernan Cortes landed
in Mexico in 1519, smallpox killed most of the natives .
In 1798, Dr. Edward Jenner noticed that milk maids, did not
develop smallpox. He hypothesized that milk maids developed
immunity to smallpox because they were exposed to cowpox, a
disease like smallpox that produces only very mild symptoms in
humans. He injected cowpox in an infected boy and it worked.
Serendipity!!!
Eureka!!!
World Health Organization
In 1967, the World Health Organization
launched a worldwide campaign against
smallpox and 11 years later, smallpox
was eliminated!!!