investigation

Question 1

Daphnia investigation

Answer 1

1) make up a range of caffeine solution of different concentration and a control solution that has no caffeine at all
2) transfer one Daphnia into the dimple on a cavity slide
3) using a pipette, place a few drops of caffeine solution onto the Daphnia
4) place the slide onto a light microscope and adjust focus
5) Count the number of heartbeat in 20 second, timed using a stopwatch

Question 2

heart rate increases as

Answer 2

caffeine concentration increases

Question 3

ethical issues of using invertebrates (daphnia)

Answer 3

• they can not give consent and may be subjected to painful procedure
• distantly related to humans