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8 Cards in this Set
- Front
- Back
- 3rd side (hint)
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What is an antigen |
A specific foreign protein found on the surface of a cell that stimulates an immune response |
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What is a pathogen? |
A disease causing microorganism |
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What are the bodies 3 defences against pathogens? |
Barriers (physical/chemical) Phagocytes Specific Response |
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Physical Barriers |
Upper epidermis of dead skin cells prevents entry of pathogens Ciliated epithelia waft trapped pathogens towards stomach to be destroyed Mucus secreted by goblet cells traps pathogens which can be expelled |
3 points |
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Chemical barriers |
Stomach acid denatures pathogens Lysozymes in eyes hydrolyse pathogens Sebum secreted by sebaceous glands in skin have antiseptic properties |
3 points |
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How do bacteria cause disease? |
Producing toxins |
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How do viruses cause disease? |
By taking over the hosts cells replicating inside them and causing cell death by bursting |
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Describe the specific response |
Phagocyte performs phagocytosis and presents pathogenic antigens on surface T cells bind to antigens and become stimulated T cells divide mitotically to form 3 types of T cells helper killer and memory T helper cells stimulate B cells T killer cells destroy body cells infected by viruses T memory cells provide long term immunity B cells engulf and present antigens on their surface T helper cells bind to this B cells are stimulated to divide by mitosis making plasma cells and memory cells Plasma cells make antibodies Memory cells provide long term immunity |
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