Unit 3: Microbiology Flashcards
What are the 3 groups
Viruses
Bacteria
Fungi
What is microbiology?
Biology of microbes and their properties and what they do.
Viruses facts
- Very small smallest type of microbe-organisms.
- You can for about 50,000 viruses side by side along 1 of a human cell.
- Cannot see them- so small. Not made out of cells.
- Don’t have cell membrane or cytoplasm.
- Not considered alive MRS GREN cannot complete.
What diseases are caused by viruses?
HIV, influenza, aids, common cold. Influenza cannot be treated with antibiotics.
Bacteria facts
- thousands of times larger than viruses. But small than plant cells.
- fit up to 500 bacteria in a row of a human cell.
- singular Bactria is called bacterium.
- bacteria NEVER HAS NUCLEUS.
Bacteria diseases
TB and cholera. can be treated by antibiotics. E.COLI- food poisoning.
Fungi facts
- Fungi not always micro organisms. Mushrooms and toadstools- quite large.
- fungus yeast does not qualify as micro organisms.
Yeast
- made of single cells.
- each cell same size as animal cell or plant cell.
- see Yeats cells through microscope.
- Yeats cell had cell membrane, cytoplasm. Nucleus and cell wall. Not made of cellulose.
Fungi diseases
Athletes foot
What should you do in the lab
Safety goggles, lab coat, disinfect hands, cover cuts or grazes, disinfect bench.
What should you do in a petri dish?
Open lid as little as possible.
Don’t breath, sneeze, or cough in the dish.
Report spillage
Bunsen burner to lift the microbes up.
3 thins you must always do after a practical
Seal dish correctly
Wash hands
disinfect bench
How to dispose petri dishes
Sterilise by heat or disinfectant before use again. Or just throw away.
What are the 5 chemicals we used to kill or stop germs spreading?
Detergents Disinfectants Sanitisers Antiseptics Antibiotics
What are detergents and what do they do?
Chemicals we use to clean surfaces. Doesn’t kill bacteria but removes em when dirt is gone.
What is disinfectant and what does it do?
Chemicals which kill bacteria on contact. Quite strong and can irritate skin. If put on dirty area, dirt may stop disinfectant reaching bacteria.
What does bacteria do on a dirty surface?
Multiplies rapidly.
What is sanitizer and what does it do?
Contains both disinfectant and detergent.
What is antiseptic and what does it do?
Kills bacteria. Milder that disinfectant. Doesn’t irritate skin. Can be put on worlds or cuts and mouth but don’t swallow.
What is antibiotics and what does it do?
Work on different way that antiseptics and disinfectants. Because of this, we can use em to treat infections.
What 4 things do you need to stop microbes from growing
Access
Food
Moisture - rig conditions to stay alive
Correct temp. - dies out of too hot
Explain how you would prevent microbes growing on a work surface in your kitchen
Clean surface daily - use 5 things. ‘muscle man’
Don’t put anything dirty on the surface or wipe afterwards.
State 4 things we can do to stop microbes growing on/in our food
Salting, pickling, fermenting, pasteurising, canning, freezing, smocking, drying, etc. (see foodtec)
How can microbes be useful?
Bread making: yeast is bacteria. ‘drunk wives’ if eat bread before cooked.
Alcohol : yeast is the drunk bit in alcohol.
Fermentation,
Cheese,
Yoghurt: bacteria lactose thicken milk into yoghurt
