daphnia practical Flashcards
1
Q
IV
A
caffeine concentration
2
Q
How vary IV
A
at least 5 - 0.01,.0.02,0.03,0.04,0.05
3
Q
DV
A
daphnia heart rate
4
Q
How measure DV
A
count heart beat under a microscope for 15 seconds
x4 for bpm
5
Q
control variable- organism
A
age
gender
species
size
6
Q
control variable- environmental
A
temperature
pH of caffeine- pH buffer
7
Q
control variable- procedural
A
volume of caffeine
acclimatisation time
8
Q
repeats
A
at least 5 for each concentration
identify and remove anomalies
calc mean
9
Q
ethical issues
A
invertebrates= underdeveloped nervous systems so no pain
reproduce quickly- little ecological effect
10
Q
why good organisms
A
transparent- heart visible to count- non invasive
caffeine can diffuse through skin- poikilothermic
