Download - Immune System
Immune System
Raffaele Nardella
Pathogens1. Bacteria
• microscopic organism -> cholera2. Viruses
• genetic material -> flu3. Fungi
• moulds and mushrooms -> athlete’s foot4. Protozoa
• single-celled organism -> infections• parasites -> malaria
Raffaele Nardella
Other causes of disease1. Vitamin deficiency
• scurvy
2. Mineral deficiency• anaemia
3. Disorders of the body• cancer - diabetes
4. Inherited deficiency• red-green colour vision deficiency
Raffaele Nardella
Body defences1. Skin
• physical damage - microbe infection - dehydration2. Blod clotting
• scab -> platelets - fibrin3.Mucous membranes
• respiratory system• nasal hairs -> keep out dust and microorganism• sticky mucus -> traps them• cilia -> carries them away
4. Stomach acid• hydrocloric acid
Raffaele Nardella
Immunity
Pathogens reproduce
cell damage (viruses) - toxins (bacteria)
Symptoms of infectious diseases
Raffaele Nardella
Immune systemWhite blood cells (lymphocytes):• Engulfing pathogens• Producing antitoxins• Producing antibodies:
proteins with chemical fit to antigensmeeting antigens
copies of antibodiesdestroying pathogens
Active immunity -> natural reproduction of antibodies
Passive immunity -> injection
Raffaele Nardella
ImmunisationVaccination -> inactive pathogen into the bodyVaccines:
• live pathogens• fragments of pathogens• toxins• dead pathogens
Acting as antigens -> white blood cell -> antibodies
Raffaele Nardella