Transcript Microorganisms organisms not visible without a microscope

Flashcard Warm-up
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Microorganisms
Very tiny (require a
microscope to be seen),
unicellular organisms that can
be found everywhere! Many
are pathogens (cause
disease) while others are
beneficial
Examples: bacteria, viruses,
protists and fungi (yeast)
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Virus
a small infectious
agent that can
reproduce only inside
a living cell (host)
Made of a nucleic
acid (DNA or RNA)
and a protein coat
(capsid)
MICROORGANISMS
ORGANISMS NOT VISIBLE WITHOUT A
MICROSCOPE
Virus: not living, smaller than
bacteria
Bacteria: prokaryotic,
unicellular
Protists: algae and protozoa
Fungi: yeast
Pathogen: a disease causing organism
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Virus:
 Structure:
a protein coat (capsid), and DNA or RNA
Lytic cycle: reproductive cycle of a
virus
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Steps of Lytic Cycle:
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1. Attaches to host cell, shape specific (shape determines who they
invade)
2. Injects DNA or RNA into host cell
3. Copies of viral DNA and capsid are made
4. Cell ruptures (lysis) and host cell dies
5. new viruses attach to neighboring cells or particles released to another
host cell
Lysogenic cycle: You sneaky virus!
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Virus enters cell and remains dormant (resting) then
goes through the lytic cycle (HIV virus, herpes virus)
Types of Viruses:
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HIV: a retrovirus (has RNA),
infects T cells, transmitted
through body fluids (except
saliva)
Influenza: the flu, infects
respiratory cells
Smallpox: has been
eradicated ! Thanks to a
vaccine! Infects lymph
nodes, lungs, then spreads
to other body parts.
Obvious sign (skin pustules)
Other Disease Causing Organisms
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Bacteria:
 Steptococcus:
strep throat
Protists that causes disease
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Plasmodia: causes malaria,
commensal relationship with
mosquito
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Vector: an organism that can transmit
the disease without getting it (like the
mosquito)
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1. infected mosquito bites human and
plasmodia enters blood stream
2. plasmodia invade liver and red
bloods cells , multiple rapidly
3. Red blood cells rupture, and invade
4. plasmodia develop into male and
females which can infect mosquitos
5. reproduction takes place in mosquitos
intestines
Malaria Symptoms:
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Headache,
shaking, chills,
fever
Fungi that cause disease
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Candida: yeast that
normally lives in our
body and starts to
multiply rapidly
 Examples:
yeast
infections, oral thrush in
babies, or kidney
infections
Ticket Out the Door:
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1. In order for a virus to reproduce it must have a _______ cell.
2. Put the following steps for the LYTIC cycle in order.
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A. Cell ruptures (lysis) and host cell dies
B. Attaches to host cell, shape specific (shape determines who they
invade)
C. new viruses attach to neighboring cells or particles released to
another host cell
D. Copies of viral DNA and capside are made
E. Injects DNA or RNA into host cell
3. A mosquito is the vector (organism transmitting) that carries the
____________ that causes malaria.
4. True or False. A microscope is not required to see all
microorganisms.
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http://health.howstuffworks.com/humanbody/systems/immune/immune-system5.htm
Flashcard Warm-up
Flashcard Warm-up
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Antigens
(the bad guys)
a substance/molecule
that, when introduced
into the body, triggers
the production of an
antibody by the
immune system
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Antibodies
(the good guys)
Proteins produced
by immune system
cells that fight off
the antigens (bad
guys)
So, how does our immune system fight
off pathogens?
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Important words to know:
Antigen: term to describe a
foreign invader
 (like
bacteria, viruses, etc.)
 AKA
the bad guys!
ANTIBODIES are the good
guys!
The “bad guys” come in all sorts of
sizes and shapes! The “good guys”
shapes match the bad guys!
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Who are the good
Guys?
Who are the bad
guys?
T-cells and B-cells are both WHITE
BLOOD CELLS!
T-cells:
initiate the immune response by
activating B-cells or destroy the
pathogen
B-cells
A. produce ANTIBODIES, proteins
that are specifically shaped to
antigens
B. memory B cells- remember the
correct antibody to protect you the
second time you are exposed
Here’s how it works:
Active Immunity: YOUR Immune
system responds to foreign invaders
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1. antigens have entered body
before and your memory B
cells already have the
antibodies
2. Vaccines: injected with
weak or dead portion, memory
B cells make antibodies
BIG IDEA!!!! Your body has
already made the antibodies
to fight this off!
Passive Immunity: is acquired! Antibodies are
passed from one person to another
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Examples:
 Mother
to child (breast milk,
placenta)
 Injected serum containing
antibodies (anti-venom)
Medicines:
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Antibiotics: treat only BACTERIAL infections
Antiviral: interfere with the life cycle of a virus
Anti-fungal: kill the fungus (tough actin’ TINACTIN)
for athletes foot
Pain killers: treat only symptoms
Health: a balanced diet provides
chemicals for immune response
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A. poor nutrition can lead to protein deficiency--B. Malnutrition: leads to a weak immune system
(which means your body can’t make the antibodies)
Flashcard Warm-up
Active Immunity
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results when exposure
to a disease organism
triggers the immune
system to produce
antibodies to that
disease.
Example: vaccinations
Passive Immunity
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The short-term immunity
that results from the
introduction of antibodies
from another person or
animal.
Example: use of antivenin, a
mother breast feeding her
baby
Case Questions:
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Operation Antibody Posters
Case 1: Before the start of the flu season, you have a flu shot. A month later you come down
with the flu. What happened?
Case 2: Dangling your legs in the ocean over the side of your raft, you feel a sharp sting on
your foot. You look down and discover a jellyfish. Soon your foot feels painful. It is swollen
and red to touch. What is happening?
Case 3: You are an immunologist and have a patient who just received a kidney transplant.
How do you explain to him that he must be given immunosuppressant drugs?
Case 4: As a child you received an emergency shot of antivenin to treat snakebite. The drug
was horse serum with antibodies. The doctor told you that these procedures could never be
repeated or boosted. Why?
Case 5: Five cases of measles suddenly appear at your high school. The school nurse is
rechecking immunization records. What could be a possible explanation for this outbreak?
(Hint: there are three possible scenarios)
Case 6: You are hurrying to finish the Biology Honors Project and ….. oops, a splinter from
your display ends up in your hand. You pull it out, but later that night your finger becomes
swollen and red. A few days later the entire hand is swollen, the pain is intense, and you
develop a fever. What’s going on?
Case 7: A friend comes to you and tells you they have the HIV virus. They can only recall
having unprotected sex ONE time, which was ten years ago. How did this happen?
Ticket Out the Door
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1. ______ are special proteins produced by B cells
that fight off pathogens.
2. ____ cells are like the general of an army, they
initiate the immune response and tell the “soldiers”
what to do.
3. A mother breast feeding her child is an example
of ________ immunity.
4. Receiving a vaccination would be an example of
_______ immunity because YOUR body is produced
the antibodies.