Topic 1

Question 1

Daphnia - IV and DV?

Controls?

Answer 1

IV - caffeine conc
DV - heart rate of daphnia
CV - Temp, volume, size, age

Question 2

Daphnia method

Answer 2

Remove one daphnia and place in cavity slide in wool
Make a range of concs ie 0 and 0.5
Pipette solution on
Place under a microscope and measure beats per minute
Repeat 5 times at each conc

Question 3

Vit C IV, DV and CV?

Answer 3

IV - fruit juice
Dv - volume of juice to decolourise DCPIP
CV - temp, conc, volume

Question 4

Vit C method

Answer 4

Measure out 1cm of DCPIP into the test tube
Titrate juice bit by bit under DCPIP turns blue to colourless
Repeat 5 times per juice

Question 5

What are the ethical issues with daphnia?

Answer 5

Simpler circulatory system but its unethical due to not giving consent and causes distress but more acceptable on invertebrates