Daphnia Experiment Report Essay

1503 Words Dec 1st, 2011 7 Pages
Daphnia Experiment Report

1. Introduction
Caffeine is found in many plant species, where it acts as a natural pesticide. It is found most commonly in cocoa, tea and coffee, but is also artificially added to some soft drinks such as cola to act as a flavour enhancer. When consumed by humans, caffeine works as a stimulant causing amounts of released neurotransmitters to be increased. High use of caffeine has been related with raised blood pressure, restlessness, insomnia and anxiety which, in the long term, can lead to heart and circulation problems.
The aim of this experiment is to observe whether caffeine has any significant effect on heart rate. To test this, daphnia will be placed in water and then caffeine solution, so the
…show more content…
|

4. Ethics
Daphnia have been used in this experiment as they have suitable characteristics that make them simple to examine in an ethical way. Daphnia are invertebrates which means no consent is needed for heart rate experiments; they have been used in testing other drugs such as pain killers and aspirin. Because they are invertebrates, they are ideal to examine because their bodies are a lot less complex than that of a mammal. They have a simple internal structure made up of antennae, eyes, abdominal organs, a heart and limbs.

A daphnia under a microscope. The heart can be seen above the cluster of eggs on the left.
A daphnia under a microscope. The heart can be seen above the cluster of eggs on the left.

The process of observing the daphnia’s heart rate is not invasive as it’s body is transparent meaning we are able to monitor the heart rate without making any incisions. Also, the experiment is made quicker by recording the heart rate for just 20 seconds at a time so that daphnia can be placed back in their natural habitat as promptly as possible.

5. Results
The following table shows the results of the experiment – four records of the daphnia’s heart rate in water and four records of the daphnia’s heart rate in caffeine solution. The average heart rate in each is shown in

Related Documents