AQA A LEVEL BIOLOGY WITH BEST SOLUTIONS what do suppressor t-cells do? - ANSWER-- halt immune response - prevent wastage of energy and resources - prevent overactive immune response - causes reduction of white blood cells after being ill d

AQA A LEVEL BIOLOGY WITH BEST SOLUTIONS what do suppressor t-cells do? - ANSWER-- halt immune response - prevent wastage of energy and resources - prevent overactive immune response - causes reduction of white blood cells after being ill define memory t-cells - ANSWER-work in the same way as memory b-cells, ensuring rapid response on subsequent exposure to the same non-self antigens define suppressor t-cells - ANSWER-regulate the immune response by suppressing activity of killer t-cells and b-cells define 'microorganism' - ANSWER-organism that is too small to be seen without a microscope define 'pathogen' - ANSWER-microorganism that causes disease outline phagocytosis - ANSWER-1. phagocyte follows conc gradient of chemoattractants 2. phagocyte attaches to pathogen 3. pathogen engulfed and placed in a vesicle (phagosome) 4. lysosomes migrate to phagosome and bind with it to form a phagolysosome --> lytic enzymes released from lysosome 5. pathogen digested 6. useful parts absorbed 7. all waste products released by exocytosis 8. non-self antigens of the pathogen displayed on the phagocytes surface (antigen-presenting) where are t-cells made? - ANSWER-thymus gland