Liquid paraffin Gas bubbles
Yeast cells in
sugar solution
Indicator
solution
Tube A
Tube B
What is the purpose of the liquid paraffin in Tube A?
Tick one box.
To prevent evaporation
To stop air getting in
To stop the temperature
going up
To stop water getting in

List five ways we are indebted to phytoplankton

Will camels hump ahrinks.give reason

Which of the following must be true for a fossil organism to be useful as an index fossil? a. the fossil organism must be widespread geographically. b. the fossil organism must be abundant. c. the fossil organism must be limited to a short span of geologic time. d. all of the above.