2. What it is…
•The immune system
enables an animal to
avoid or limit any
infections.
•The Immune System
has 2 different
defense systems–
Innate and Acquired
http://hobokenwomensassociation.blogspot.com/2009/09/t
en-ways-to-strengthen-your-immune.html
3. Innate Immunity
Barrier Defenses: Internal Defenses:
• Skin- an outer covering • Phagocytic cells(types of
which provides a significant White Blood Cells)- A cell that
ingests microorganisms and
obstacle to invasion by the foreign particles.
microbes that are present • Inflammatory response- the
on the body. changes brought about by
• Mucous membranes- Form signaling molecules released
upon injury or infection
physical barriers that bar
• Natural killer(NK) cells- help
the entry of microorganisms
recognize and eliminate
and viruses certain diseased cells in
vertebrates
4. Acquired(Adaptive) Immunity
• Humoral response
– Antibodies defend against
– Infection of body fluids
• Cell-mediated response
– Cytotoxic lymphocytes
defend against infection in
http://hplusmagazine.com/sites/default/files/ima
body cells ges/articles/jan10/influenza-virus-antibodies.gif
5. Acquired Immunity Defends against
infection of body cells and fluids
• Helper T Cells- makes CD₄- a • Active Immunization-
response to nearly all vaccine which is a
antigens nonpathogenic form of a
microbe
• Cytotoxic T Cells-make CD₈-
• Passive Immunity- provides
response to infected cells immediate, short term
• B Cells- generate antibody- protection
secreting plasma cells- • Immune Rejection- certain
response to extracellular vaccinations could be
pathogens rejected due to persons
blood type
