Paper 1

Question 1

Explain how you could calculate the size of bacteria population in a culture of 100ml? 6 marks

Answer 1

1) Take 0.1ml of a liquid using a pipette and place i on a slide. Use a light microscope and count the number of visible bacteria you can see.
2) Times the count by 1000- this is a estimate. Repeat 5 times to get an average x1000

Question 2

Describe the differences between prokaryotes and eukaryotes in regards to their DNA?

Answer 2

Pro- have a single loop of DNA suspended in the cytoplasm.

Euk- have membrane bound organelles and have linear and double stranded DNA

Question 3

How many micrometers in a mm?

Answer 3

1micrometer= 0.001 mm