CH. 24. The Immune System

Transcription

1 CH. 24 The Immune System

2 The immune systems consists of organs, cells, and molecules that fight infections and protect us from invaders. Pathogens: Bacteria, Viruses, Parasites, Fungi 1. 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 1 st 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 31.4 Immunity and Technology 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 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 Phagocyte Pseudopod E. Coli For internal use only, property of Coulter Corporation

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

10 31.4 Immunity and Technology 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 31.4 Immunity and Technology 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 antigen bacteria

15 Acquired Immunity B cells antibodies Activated divide B Cell Plasma

16 ACQUIRED IMMUNITY B CELLS B Cell Memory B Cell

17 ACQUIRED IMMUNITY ACTIVATED T CELL Killed by HIV Attack things outside the cell antibodies HELP HelperT Cell B cell HELP Cytotoxic T Cell 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 response 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 Cytotoxic T Cell Tumor Cell Skeleton 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 causes memory cells to be produced allows immune system to respond quickly to infection has such a fast response, a person will not get sick memory B cells Antigens in a vaccine trigger an immune response, and memory B cells are made. A memory B cell is stimulated when the real pathogen binds to it. The B cell quickly activates and makes antibodies that fight the pathogens before you 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 Research and answer questions on separate paper or print answers.

28 Immunity Acquired Acquired resistance to infection Innate 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 active immunity Induced Active Immunity Natural Passive Immunity Artificial Passive 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)