Download Ch 40 Immune System ppt

A.
Pathogen: a disease-causing agent
Examples are:
viruses, bacteria, protists, & fungi
B. Antigen: substance on the surface of the
pathogen that triggers an immune response.
Antigens can be carbs, lipids, or proteins.
A. Direct Contact includes:
handshake, kissing, sexual contact
B. Indirect Contact includes:
food, water, vectors, contact with
surfaces
Tries to keep all pathogens out. It’s like our
fortress walls protecting us. If an enemy enters,
then a generalized defense occurs first.
1st line of defense includes:
A. skin, saliva, mucous
2nd line of defense includes:
B. Inflammatory response = redness,
swelling, fever
C. Interferons: proteins produced by
cells infected with a virus. They slow viral
replication.
If a pathogen is able to get past the body’s
nonspecific defenses, the immune system reacts
with a series of defenses that attack the exact
pathogen. These defenses include white blood
cells and antibodies.
Humoral Immunity: immunity against
pathogens in the body fluids (Page 1037)
1. White blood cells, leukocytes, are the
main immune cells defending the body. There are
many types of wbc’s including:
*B-cells
*Memory cells
*Helper T-cells
*Suppressor T-cells
*Killer T-cells
*Macrophages
A.
2. Antibodies: specialized proteins produced
by B-cells that help destroy pathogens
A.
Active Immunity: when the body makes its
own antibodies in response to an antigen.
Is acquired after illness or vaccination.
B.
Passive Immunity: If antibodies produced
by another animal are injected into the
bloodstream.
*Another example would be when a mother
passes her antibodies through the placenta or
during nursing.