Unit 3: Microbiology

Question 0

What are the 3 groups

Answer 0

Viruses
Bacteria
Fungi

Question 1

What is microbiology?

Answer 1

Biology of microbes and their properties and what they do.

Question 2

Viruses facts

Answer 2

• 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.

Question 3

What diseases are caused by viruses?

Answer 3

HIV, influenza, aids, common cold. Influenza cannot be treated with antibiotics.

Question 4

Bacteria facts

Answer 4

• 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.

Question 5

Bacteria diseases

Answer 5

TB and cholera. can be treated by antibiotics. E.COLI- food poisoning.

Question 6

Fungi facts

Answer 6

• Fungi not always micro organisms. Mushrooms and toadstools- quite large.
• fungus yeast does not qualify as micro organisms.

Question 7

Yeast

Answer 7

• 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.

Question 8

Fungi diseases

Answer 8

Athletes foot

Question 9

What should you do in the lab

Answer 9

Safety goggles, lab coat, disinfect hands, cover cuts or grazes, disinfect bench.

Question 10

What should you do in a petri dish?

Answer 10

Open lid as little as possible.
Don’t breath, sneeze, or cough in the dish.
Report spillage
Bunsen burner to lift the microbes up.

Question 11

3 thins you must always do after a practical

Answer 11

Seal dish correctly
Wash hands
disinfect bench

Question 12

How to dispose petri dishes

Answer 12

Sterilise by heat or disinfectant before use again. Or just throw away.

Question 13

What are the 5 chemicals we used to kill or stop germs spreading?

Answer 13

Detergents
Disinfectants
Sanitisers
Antiseptics
Antibiotics

Question 14

What are detergents and what do they do?

Answer 14

Chemicals we use to clean surfaces. Doesn’t kill bacteria but removes em when dirt is gone.

Question 15

What is disinfectant and what does it do?

Answer 15

Chemicals which kill bacteria on contact. Quite strong and can irritate skin. If put on dirty area, dirt may stop disinfectant reaching bacteria.

Question 16

What does bacteria do on a dirty surface?

Answer 16

Multiplies rapidly.

Question 17

What is sanitizer and what does it do?

Answer 17

Contains both disinfectant and detergent.

Question 18

What is antiseptic and what does it do?

Answer 18

Kills bacteria. Milder that disinfectant. Doesn’t irritate skin. Can be put on worlds or cuts and mouth but don’t swallow.

Question 19

What is antibiotics and what does it do?

Answer 19

Work on different way that antiseptics and disinfectants. Because of this, we can use em to treat infections.

Question 20

What 4 things do you need to stop microbes from growing

Answer 20

Access
Food
Moisture - rig conditions to stay alive
Correct temp. - dies out of too hot

Question 21

Explain how you would prevent microbes growing on a work surface in your kitchen

Answer 21

Clean surface daily - use 5 things. ‘muscle man’

Don’t put anything dirty on the surface or wipe afterwards.

Question 22

State 4 things we can do to stop microbes growing on/in our food

Answer 22

Salting, pickling, fermenting, pasteurising, canning, freezing, smocking, drying, etc. (see foodtec)

Question 23

How can microbes be useful?

Answer 23

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

Question 24

Hw do you prevent milk from getting bacteria?

Answer 24

Heated for 70 degrees Celsius for 15 seconds. Which kills most batterie. Called pasteurisation.

Question 25

How do you sterilise milk and why?

Answer 25

Milk contains sugar (lactose) and protein. You can sterilise it by heating it up to 80 degrees Celsius to kill any microorganisms in it.

Question 26

What is the lag phase

Answer 26

The first two hours, when yeast abuses to new conditions.

Question 27

What is the growth phase

Answer 27

When yeast divides very rapidly and few are dying

Question 28

What is the stationary

Answer 28

8-12 hours cells dividing and dying

Question 29

What is the death phase

Answer 29

After 12 hours. Many cells are dying