1. CH. 24
The Immune System

2. Pathogens: Bacteria, Viruses, Parasites, Fungi
The immune systems consists of organs, cells, and molecules that fight infections and protect us from invaders.
Pathogens: Bacteria, Viruses, Parasites, Fungi
Innate (nonspecific) immunity – present at birth; not specific for the invader
2. Acquired (specific) immunity – develops throughout life; specific for the invader

3. Innate Immunity External Barriers – 1st line of defense
Skin, sweat – good pH, digestive enzymes
Mucus membranes – good trap, digestive enzymes
Tears – good trap, digestive enzymes
Stomach acid – good pH, digestive enzymes

4. Antibiotics and antiseptics cause pathogens to burst.

5. The immune system has many responses to pathogens and foreign cells that pass the initial barriers.

6. Phagocytic cells – capture and digest (lysozyme)
Innate Immunity
Phagocytic cells – capture and digest (lysozyme)
Macrophages – blood and tissue, long lives
Neutrophils – most abundant in blood, short lives
Eosinophils – specialty is parasite
Dendritic cells – connection to the acquired immune response
Natural Killer Cells
Attack virus-infected, cancer cells
Kill by poking holes in abnormal cells (cytotoxic)

7. White blood cells (Leukocytes/ Lymphocytes) attack infections inside the body.
Phagocytes engulf and destroy pathogens.
pseudopods
E.coli

8. Phagocyte Reaches Out To Capture Bacteria
Pseudopod
E. Coli
For internal use only, property of Coulter Corporation

9. Phagocyte Draws Bacteria in for Phagocytosis
E. Coli
Pseudopods
For internal use only, property of Coulter Corporation

10. In fever, body temperature increases.
Low fevers stimulate white blood cells to mature.
High fevers can cause seizure, brain damage, and even death.

11. Innate Immunity- Nonspecific Responses to pathogens
Inflammation – redness and heat
Fever
Antimicrobial – kill or stop reproduction
complement – pokes holes in invading cells
Interferons – anti-viral

12. Acquired (SPECIFIC) Immunity
Acquired immunity allows specific recognition of any invader
(has specific receptors)
Acquired immunity provides memory to the immune response

13. T helper T cytotoxic antibodies
Acquired Immunity: two specific immune responses.
T cells destroy infected cells.
B cells produce antibodies.
T Cells B Cells
T helper T cytotoxic antibodies

14. Acquired Immunity (SPECIFIC)
Specific immune responses begin with the detection of antigens.
Receptors are proteins which recognize a single type of molecule - the antigen, which is found on foreign material
bacteria
antigen

15. Acquired Immunity B cells
antibodies
Plasma Cells
B Cell
Activated
divide

16. Acquired Immunity B cells
MemoryB Cell
B Cell

17. Acquired Immunity Activated T cell
Attack things outside the cell
antibodies
Killed by HIV
HelperT Cell
HELP
B cell
Cytotoxic T Cell
HELP
Kill infected & cancer cells (when in or on your own cell)

18. Acquired Immunity- Memory cells
The next time this memory cell sees this antigen:
Primary
response
Secondary
Primary exposure
secondary exposure

19. Cytotoxic T Cells Attack A Tumor Cell
part I
Tumor Cell
Cytotoxic T Cell
For internal use only, property of Coulter Corporation

20. Cytotoxic T Cells Attack A Tumor Cell
part II
Tumor Cell
Cytotoxic T Cell
For internal use only, property of Coulter Corporation

21. Cytotoxic T Cells Attack A Tumor Cell
part III
Tumor Cell Skeleton
Cytotoxic T Cell
For internal use only, property of Coulter Corporation

22. Vaccines artificially produce acquired immunity.
Vaccines also control pathogens and disease.
given to prevent illness
contain the antigen of a weakened pathogen

23. Vaccination provides immunity. stimulates a specific immune response
Antigens in a vaccine trigger an immune response, and memory B cells are made. 1
memory B cells
causes memory cells to be produced
A memory B cell is stimulated when the real pathogen binds to it. 2
allows immune system to respond quickly to infection
The B cell quickly activates and makes antibodies that fight the pathogens before you get sick. 3
has such a fast response, a person will not get sick
Vaccination animation

24. HIV Virus Attacks a T Cell
For internal use only, property of Coulter Corporation

25. Diseases and the Immune System
Our immune system can tell the difference between foreign and self – when it can’t  autoimmune disease
Diabetes
Multiple sclerosis
arthritis
Sometimes we over react to things that are foreign but not harmful  allergy
Asthma
Food allergy
Hives

26. Diseases and the Immune System
Sometimes our immune system is depleted or destroyed
Stress
HIV/AIDS
Sometimes we want something foreign to be tolerated but it gets destroyed by our immune system
Blood transfusions
Organ transplants

27. HIV and AIDS webquest- Due Friday, 3/9!
Go to Holt textbook website: Ch. 31
Research and answer questions on separate paper or print answers.

28. Immunity Acquired Innate Active Immunity Passive Immunity
Acquired resistance
to infection
Inborn resistance
to infection
Active Immunity
Passive Immunity
Produced by antibodies
that develop in our bodies
in response to antigen
Produced by transfer
Of antibodies from
Another source
Natural
Passive Immunity
Artificial
Passive Immunity
Natural active
immunity
Induced
Active Immunity
Develops after exposure to
Antigens (contact with sick
Person)
Develops after administration
to of Antigens to prevent
Disease (vaccination)
Conferred by transfer of
Maternal antibodies across
Placenta or breast milk
Conferred by administration
Of antibodies to combat
Infection (immunoglobulin
Shot)