Untitled 47 [] · Untitled 47 Author: cody peery Created Date: 8/3/2017 3:47:28 PM ...
Chapter 47- Non Specific Defenses - Mrs. Rasmussen...
Transcript of Chapter 47- Non Specific Defenses - Mrs. Rasmussen...
•1 The Germ Theory of Disease
infectious diseases were caused by germs.
Chapter 47- Non Specific Defenses
Immune System
Diseases are caused by pathogens.
•A disease is any change, other than an injury, that disrupts the normal functions of the body.
• Pathogens are destroyed by the body’s immune system.
attacks and “remembers” each pathogen
• Agents of Disease
•viruses•bacteria•protists•worms•fungi
•Diseases Are Spread by– coughing– sneezing – physical contact – contaminated water or food – infected animals
Transmission of Disease1. Direct Contact – touching an infected person
2. Indirect Contact – touch infected surfaces or breath in pathogens from the air.
3. Ingestion – drinking contaminated water or eating contaminated food
• Vectors- organism that carries diseases and bites you.
1st Line of Defense - Nonspecific
• JOB- keeps pathogens out of the body. • Skin-
• Most Important• Mucus and sweat • Cilia in the nose
• Tears• Stomach acid and digestive enzymes
•Second line of Defense: Specific Defenses
When activated by a pathogen it’s called an immune response. Any substance, such as a virus or bacterium, that triggers this response is known as an antigen.
•If a pathogen enters the body it makes an inflammatory response.
-is a non-specific defense reaction to tissue damage caused by injury or infection.
•Histamines Released-increase blood flow to injured area
•Phagocytes- ingest and destroy pathogens and foreign matter•Neutrophine•Macrophage•Natural Killer cells
• Antibodies which are proteins that recognize and bind to an antigen marking it for destruction.
• Memory cells- remember pathogens• B lymphocytes (B cells)-defend the body against antigens and pathogens in body fluids.
• T lymphocytes (T cells)-defend the body against abnormal cells and pathogens inside living cells.
Antigen
Antibody
Second Line of Defense - NonspecificInflammatory Response1. Damaged tissues release histamines, increasing blood
flow to the area.2. Histamines cause capillaries to leak, releasing phagocytes
to the wound.3. Phagocytes engulf bacteria and destroy it4. Platelets move out of the capillary to seal the wounded
area.
Skin
Phagocytes move into the area and engulf the bacteria and cell debris
Capillary
Bacteria enter the wound
Wound
•17 There are three different types of immune system disorders:
•18 There are three different types of immune system disorders:
• allergies
•19 AllergiesAn overreaction to a common
antigen.
pollen, dust, mold, and bee stings.
autoimmune disease
the body attacks itself.• Some examples of autoimmune diseases
include:• Type I diabetes
• Rheumatoid arthritis
•22 Immunodeficiency Diseases
a weakened immune response
•23 Immunodeficiency Diseasescan be
caused by the HIV virus.
•24 HIV attacks and destroys “helper” T-cells.
•As the number of helper T cells decreases, the body becomes more susceptible to other diseases.