1. Immune System Part II Physiology Standards: 10 a-e
Once inside the body pathogens are met with several defense systems

2. The Immune System Nonspecific defenses continued
If the skin is “broken” you will get what is called the inflammatory response
Blood flow is increased as millions of white blood cells flood the infected area
An elevated body temp. (fever ) is another form of defense creating a poor environment for pathogens
A fever of 100 degrees F causes white blood cells to mature quicker while a fever of 103 or higher could cause some serious damage or even death

3. The Lymphatic System
Your immunes system’s “pipeline” for transporting and housing specialized cells for fighting infections are found in your lymphatic system

4. The Immune System Specific Defenses of the Immune System
When the body attacks foreign objects that have made it into your body it is called the immune response
A substance that “triggers” an immune response is known as an antigen
There are two types specialized cells that attack antigens
B~ lymphocytes (B-cells)-produce proteins that inactivate pathogens that have not infected cells yet
T~ lymphocytes (T-cells)-destroy body cells that are infected with pathogens

5. Antibodies Antigen binding sites Antigen Antibody
B~ lymphocytes are responsible for making antibodies which are specialized proteins that are specifically designed to destroy specific pathogens by recognizing antigen binding sites

6. Antibodies
Antibodies are proteins that recognize and “bind” to antigens
Once the infection is destroyed, memory B-cells remain capable of producing that specific antibody in case you receive the same infection
It is estimated that a healthy adult has around 100 million different types of antibodies to fight infection
The more “exposure”, the more antibodies you create in your “library”

7. B Cells & Humoral Immunity
Antibodies “clump” the antigens and phagocytes “eat” the pathogen clumps
Surface proteins on antigens trigger memory B Cell production
Activated B cells release millions of antibodies

8. T Cells – “Pathogen Destroyers”
Once an antigen or infected cell is in the body T Cells use their surface proteins to recognize the antigen and start making more T Cells
Activated T Cells remain in the body forever waiting for a future invasion
T Cells use many methods to “kill” the antigen or infected cell directly

9. Acquired Immunity
Humans have long wanted to prepare people before they become infected with a disease, especially when the disease could potentially kill them
A vaccination can be a:
A weakened form of the original pathogen
A “killed” pathogen that still has it’s shape for the immune response
An alternate form of the disease such as cowpox to trigger the immune response for smallpox

10. Acquired Immunity Two Types of Immunity:
Antigens in a vaccine trigger
the immune response and
Memory B Cells are made
Two Types of Immunity:
Active Immunity – the type of immunity that is generated by the body following exposure to a pathogen or after a vaccination
Passive Immunity – can be utilized by injecting antibodies to the infection that were created by another animal

11. Diseases that Weaken the Immune System
Your immune system is your internal defense system against all infections and pathogens, right?
What happens if a pathogen attacks your Immune System?
Leukemia is cancer of the bone marrow
Leukemia weakens bones and makes them unable to produce disease fighting white blood cells
HIV (Human Immunodeficiency Virus) is another

12. HIV kills T-Cells until the host’s immune system is so weak that the host is unable to fight off mild infections
HIV
HIV enters the body through direct contact and sharing of blood or fluids