Practicals

Investigate the effect of caffeine on heart rate in Daphnia

Investigate the effect of caffeine on heart rate in Daphnia

• Independent variable: range of 5 diff caffeine concentrations

• Place Daphnia on cotton wool (to reduce movement) on microscopic slide

• Add drop of caffeine solution onto Daphnia

• Measure heart rate in bpm

• Repeat for different conc of caffeine

• See if there’s correlation between caffeine conc & heart rate

• Repeat with different daphnia

• Control variable: species, age/size, temperature

Investigate vitamin C content of fruit juice

• Place known volume & conc of DCPIP in a conical flask under burette

• Measure the volume of fruit juice required to turn DCPIP from blue to colourless

• Repeat at least 3 times

• Repeat titration with a range of know conc of vitamin c and produce a standard curve

• Compare juice titration volumes to calibration curves to interpolate their vitamin C content.

Ethical issues regarding use of invertebrates in research - FOR

• Rights of humans to live healthy lives

• Improve the health of humans

Ethical issues regarding use of invertebrates in research - AGAINST

• Rights of animals not to be harmed

• Morally wrong to harm animals

• Animals not able to give consent

• No bad action should be carried out