Nonspecific immune defenses The immune system protects your body from pathogens
Jan 13, 2016
Nonspecific immune defenses
The immune system protects your body from pathogens
Resistance
• Resistance is your bodies ability to defend against pathogens.
• Your immune system gives you resistance.
physical barriers to disease
• Nonspecific defense.– Sweat, oils, &
waxes.– Mucous
membranes.– HCL of stomach.
Why you get a fever
• Pathogens that attack human body like 98.6° F best.
• Raising temperature of body increases effectiveness of white blood cells.
• Decreases effectiveness of pathogen.
Interferon
• Chemical released by cells infected by viruses.
• Causes surrounding cells to resist infection.
Inflammatory Response
• Symptoms:– Redness– Heat– Swelling, pain
• What occurs:– Damaged cells
release histamines.
– Causes vasodialation
– Causes increase in permeability.
•Inflammatory response occurs when pathogen penetrates the skin.
Pair share: explain this picture to your partner. What is happening in each frame?
Neutrophils
• Most common white blood cell
• Kill pathogens using phagocytosis.
• Circulate in blood stream.
• Migrate towards site of infection.
• Move out of the blood stream
Macrophages
• Stationed in certain tissues.• Destroy by phagocytosis.• Rid the body of debris and damaged cells.
Natural Killer Cells
• Attack cells which have been infected by pathogen.
• Kills cancer cells.
• Kills by puncturing cell membrane.
summary
1. List 3 nonspecific defense barriers.
2. List 3 symptoms of the inflammatory response.
3. What do macrophages do?