1. Immune System

2. Pathogens: Disease-causing agents
Examples:
Viruses, Bacteria, Protozoans, Fungi
Main sources of pathogens are:
Soil
Contaminated Water
Infected Animals
People
For the most part fungi are not harmful to humans. Some fungi can parasitize humans and other animals. For example, athletes foot, ring worms, yeast infections, are infections in humans that are caused by several species of fungi.
Malaria protist releasing spores

3. Vectors for Pathogens Pathogens can be transmitted by
Air, direct contact, an object, or by a vector
Most common vectors are insects
Malaria is spread by mosquitoes
Lyme disease spread by ticks
Bubonic plague spread from rats to
humans by fleas
When a mosquito that has malaria bites you, the parasite is released into the blood stream to infect liver cells. The parasite replicates in the liver cells. The parasite causes the liver cells to burst and is released into the blood stream to infect many more new red blood cells. This causes fatigue, chills, nausea,

4. Viruses vs. Bacteria Virus Bacteria Non-living organism
Contains genetic material (either DNA or RNA)
Have no organelles
Contains a protein coat
Can not replicate on their own
Living organism
Prokaryotic organisms
Contains genetic material (Circular DNA)
Replicates by binary fission.

5. VIRUSES WHAT IS A VIRUS: "Viruses exist in two distinct states.
Without a host cell, the virus remains entirely dormant (Nonliving status).
no internal biological activities occurring within the virus; referred to as 'virions
When the virion comes into contact with a host, it becomes active (living) and is then referred to as a virus.
It now displays properties of living organisms, such as reacting to its environment and directing its efforts toward self-replication“ *STERNGRR*

6. Picture of a virus common viral diseases include: Chickenpox.
Flu (influenza)
Herpes.
Human immunodeficiency virus (HIV/AIDS)
Human papillomavirus (HPV)
Identify if/ what vaccinations are available.
The outer layer of all viruses are made of proteins- capsid. Inside the capsid is the genetic material, this can either be DNA or RNA, but never both.

7. Pictures of Viruses Bacteriophage-infects bacteria
Adenovirus-common cold
Influenza virus-Flu

8. How does a virus make me sick?
In order to replicate a virus must come into contact with a host cell, it can’t survive on its own. A virus basically tricks your cells into thinking that it belongs in your cells. The virus attaches to a receptor on your cell membrane like a puzzle piece. Once it attaches to the host cells cell membrane, it inserts its DNA into the host cell, like inserting an IV into your arm. The virus then has two paths that it can take, the lytic cycle or the lysogenic cycle.
In the lytic cycle, the host cell will make many copies of the viral DNA or RNA and make new capsids to surround the viral DNA or RNA. The new virus will then cause the host cell to burst (lyse) so that it can leave the host cell and infect other cells. How can you tell the difference? Cells in the lytic cycle, generally show symptoms right away.
In the virus enters into the lysogenic cycle (the second path), the viral DNA will go straight to the nucleus and incorporate itself into a chromosome in the host cell (just like recombinant DNA). The virus will then just sit here dormant until something (maybe environmental trigger) activates it and will then enter into the lytic cycle and begin to replicate more viruses. Herpes is an example of a virus that causes a latent infection.
p. 480

9. Retroviruses Some viruses have RNA instead of DNA. HIV is a retrovirus
When retroviruses enter into host cells, enzymes transcribe DNA from the viral RNA in the cytoplasm.
The DNA then goes into the nucleus of the host cell and incorporates itself into a chromosome.

10. Bacteria
Bacteria are examples of the prokaryotic cell type. An example is E. coli. In general, prokaryotic cells are those that do not have a membrane-bound nucleus. In fact "pro-karyotic" is Greek for "before nucleus".

11. Only a small percentage of bacteria cause disease.
Bacteria causes disease in 2 ways.
Destroy living cells and tissues of infected organisms
2. Release toxins that interfere with the normal activity of the host cell.
TUBERCULOSIS
Bacteria that causes disease can do this in 2 ways. The bacteria that causes tuberculosis destroys large areas of tissues when it is inhaled into the lungs.When a bacteria releases toxins it interferes with the normal activity of the cell. Botulism is a severe type of food poisoning caused by releasing toxins into the host cells.
BOTULISM

12. Non-Specific Defenses
First Line of Defense
The skin is the most important barrier against infection. Very few pathogens can penetrate the layers of the skin.
The Second Line of Defense
If pathogens enter the body you get an…
Inflammatory response - nonspecific reaction to tissue damage, produces white blood cells to fight infection.
-Your blood vessels dilate (area becomes red and swollen) to allow more blood flow to the area and more white blood cells move in to engulf and destroy bacteria.

13. Specific Defenses
Antigens - proteins found on the surface of pathogens (bacteria, viruses, fungi, pollen) that cause an immune response.
Antibodies - proteins found on the surface of white blood cells that attach to an antigen
-Antibodies recognize and binds to it like a lock and key
Video Clip – inside ralphie -

14. Active Immunity
Active Immunity – type of immunity produced by the body’s response to a vaccine/exposure to a pathogen.
Vaccination – injection of a mild or weakened form of
a pathogen.
- vaccine stimulate the body to make millions of
plasma cells to produce antibodies.
ex. Smallpox vaccines, chickenpox vaccine
Vaccine video -
This type of immunity is permanent! You are
protected from this disease for the rest of your life.

15. Passive Immunity – short term immunity caused by antibodies produced by other animals for when a pathogen is injected into the body.
- ex. mother to fetus
Only lasts a short time because the immune system
does not learn how to make the antibodies!

16. Treatments Antiobiotics – kills or slows down the growth of bacteria
When antibiotics are not properly used, it can lead to antibiotic resistance.
Anti-viral – does not destroy virus, but slows down the production of new viruses
how the flu invades a cell and how the antiviral (Tamiflu) works to stop it (I would mute it and read the steps to the class) 
why antivirals are important