Investigation: effect of caffeine on the heart rate of Daphnia
Hypothesis
If the concentration of caffeine is increased, then the heart rate of Daphnia would then
increase. Caffeine is a stimulant so Daphnia's heart rate would increase when exposed to
the caffeine solution
Aim
Prove that an administration of caffeine on Daphnia has a close-to-immediate positive effect
on the heart rate of Daphnia, this is due to the fact that caffeine is a stimulant which affects
heart rate due to the release of hormones. The objective of this investigation is to investigate
the effect of caffeine on Daphnia.
Proposal
I am proposing to investigate the effect of caffeine on Daphnia. If caffeine is added to
distilled water, this would increase the heart rate of Daphnia. My investigation involves
making various concentrations of caffeine solutions to observe the effects caffeine has on
heart rate. This experiment also relates to the effects of stimulants on the human body.
Daphnia have a thin permeable membrane, this would make it easier to count the heat beats
with ease.
Health and safety
As I would be conducting my practical in the laboratory, there are necessary precautions that
need to be taken to minimise the risk of harm to myself and others around me. Coming into
contact with a range of chemicals such as acids can lead to severe burns to the skin, taking
necessary precautions reduces the possibility of a fire, or other severe health risks.
Personal protective equipment must be worn throughout the duration of the practical to
reduce the risk of harm to myself or others in the laboratory. Personal protective equipment
includes: - disposable gloves - laboratory coat - eye protection. Covered shoes should be
worn and hair would have to be tucked and tied to reduce further risk of injury.
Plan - Investigate the effects of caffeine on Daphnia
6
, Aim: Prove that an administration of caffeine on Daphnia has a close-to-immediate positive
effect on the heart rate of Daphnia, this is due to the fact that caffeine is a stimulant which
affects heart rate due to the release of hormones. The objective of this investigation is to
investigate the effect of caffeine on Daphnia.
Hypothesis:
If the concentration of caffeine is increased, then the heart rate of Daphnia would then
increase. Caffeine is a stimulant so Daphnia's heart rate would increase when exposed to
the caffeine solution.
Variables:
Independent:
● Caffeine concentration (M)
Dependent:
● Heart rate of Daphnia
Control:
● Volume of solution - the same number of drops should be used each time.
● Size of daphnia - the size of the daphnia should be around the same size for repeats.
● Acclimatise time - Daphnia should be left in a caffeinated solution for the same
amount of time to acclimatise.
Risk assessment
Hazard Risk Safety precautions to take In emergency Risk
level
Biohazard Contamination Disposable Latex gloves must be Lab technician must be Low
worn throughout the duration of notified.
practical - hands should be
washed with soap after handling
daphnia.
Broken glass Injury from Caution should be taken when Glass shouldn't be Low
sharp object handling glassware, it should be removed from wound,
kept away from the edge of the medical assistance must
worktop. be sought
Chemicals - Flammable, Eye protection must be worn Lab technicians must be Medium
Ethanol irritant to skin throughout the practical, room notified, necessary action
and eyes must be well ventilated and should be taken.
ethanol should not be used near
naked flames.
Equipment:
7
Hypothesis
If the concentration of caffeine is increased, then the heart rate of Daphnia would then
increase. Caffeine is a stimulant so Daphnia's heart rate would increase when exposed to
the caffeine solution
Aim
Prove that an administration of caffeine on Daphnia has a close-to-immediate positive effect
on the heart rate of Daphnia, this is due to the fact that caffeine is a stimulant which affects
heart rate due to the release of hormones. The objective of this investigation is to investigate
the effect of caffeine on Daphnia.
Proposal
I am proposing to investigate the effect of caffeine on Daphnia. If caffeine is added to
distilled water, this would increase the heart rate of Daphnia. My investigation involves
making various concentrations of caffeine solutions to observe the effects caffeine has on
heart rate. This experiment also relates to the effects of stimulants on the human body.
Daphnia have a thin permeable membrane, this would make it easier to count the heat beats
with ease.
Health and safety
As I would be conducting my practical in the laboratory, there are necessary precautions that
need to be taken to minimise the risk of harm to myself and others around me. Coming into
contact with a range of chemicals such as acids can lead to severe burns to the skin, taking
necessary precautions reduces the possibility of a fire, or other severe health risks.
Personal protective equipment must be worn throughout the duration of the practical to
reduce the risk of harm to myself or others in the laboratory. Personal protective equipment
includes: - disposable gloves - laboratory coat - eye protection. Covered shoes should be
worn and hair would have to be tucked and tied to reduce further risk of injury.
Plan - Investigate the effects of caffeine on Daphnia
6
, Aim: Prove that an administration of caffeine on Daphnia has a close-to-immediate positive
effect on the heart rate of Daphnia, this is due to the fact that caffeine is a stimulant which
affects heart rate due to the release of hormones. The objective of this investigation is to
investigate the effect of caffeine on Daphnia.
Hypothesis:
If the concentration of caffeine is increased, then the heart rate of Daphnia would then
increase. Caffeine is a stimulant so Daphnia's heart rate would increase when exposed to
the caffeine solution.
Variables:
Independent:
● Caffeine concentration (M)
Dependent:
● Heart rate of Daphnia
Control:
● Volume of solution - the same number of drops should be used each time.
● Size of daphnia - the size of the daphnia should be around the same size for repeats.
● Acclimatise time - Daphnia should be left in a caffeinated solution for the same
amount of time to acclimatise.
Risk assessment
Hazard Risk Safety precautions to take In emergency Risk
level
Biohazard Contamination Disposable Latex gloves must be Lab technician must be Low
worn throughout the duration of notified.
practical - hands should be
washed with soap after handling
daphnia.
Broken glass Injury from Caution should be taken when Glass shouldn't be Low
sharp object handling glassware, it should be removed from wound,
kept away from the edge of the medical assistance must
worktop. be sought
Chemicals - Flammable, Eye protection must be worn Lab technicians must be Medium
Ethanol irritant to skin throughout the practical, room notified, necessary action
and eyes must be well ventilated and should be taken.
ethanol should not be used near
naked flames.
Equipment:
7
