• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

The effect of caffeine on the heart rate

Extracts from this document...

Introduction

The effect of caffeine on heart rate Aim: To investigate the effect of caffeine on the heart rate of Daphnia (water fleas). Introduction: Plants produce caffeine as an insecticide. Cocoa in South America, coffee in Africa and tea in Asia have all been used for hundreds of years to produce 'pick me up' drinks containing caffeine. These days, caffeine is also used as a flavour enhancer in a wide range of cola and other soft drinks. ...read more.

Middle

This can lead to heart and circulation problems. Daphnia are small, planktonic crustaceans commonly called water fleas because of their saltatory swimming style (although fleas are insects and thus only very distantly related). They live in various aquatic environments ranging from acidic swamps to freshwater lakes, ponds, streams and rivers. Hypothesis: Caffeine will increase the heart rate of the Daphnia (water fleas). Equipment needed: * Culture of Daphnia (water fleas) * Cavity slides * Dropping pipettes * Distilled water and pond water * Caffeine solution * Cotton wool * Standard glassware (beakers, measuring cylinders etc.) ...read more.

Conclusion

Trial 1 Trial 2 276 241 100 180 156 50 65 72 0 This graph shows that as the concentration of caffeine increases the heart rate increases too. Conclusion: Daphnia are small, planktonic crustaceans commonly called water fleas. I believe my hypothesis are right shown that my results presents that. Caffeine acts as a stimulant drug, causing increased amount of stimulatory neurotransmitters to be released therefore the heart rate increases. My results may not be 100% accurate due to the change of temperature in the room. My results are reliable because I repeated twice and the difference between them is not too big therefore my results are valid. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Energy, Respiration & the Environment section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Here's what a star student thought of this essay

3 star(s)

Response to the question

The piece is done well. Whilst simplistic in format the essay has components of research and analysis of the results which are presented well. Expansion on the conclusion and evaluation are needed to show a deeper understanding and improvement of ...

Read full review

Response to the question

The piece is done well. Whilst simplistic in format the essay has components of research and analysis of the results which are presented well. Expansion on the conclusion and evaluation are needed to show a deeper understanding and improvement of the experiment.

Level of analysis

The introduction and aim are done well, and define the effects of caffeine that the candidate would expect to see in the daphnia, although they do not use any research that has previously been used on the fleas which would have been good for the author to use this in the background to the water fleas to adjust their hypothesis if needed and work out dosages for the fleas. I'm not sure how well the results can be assessed because the amount of beats assessed under a microscope on that small a specimen would be inaccurate. However, the graphs are good as they show a good correlation between their research and what actually happened. They do not show any improvements for the experiment which would have been good to show a deeper understanding of the principles behind the experiment.

Quality of writing

Punctuation, grammar and spelling all good. Tone and format of the piece correct and clear.


Did you find this review helpful? Join our team of reviewers and help other students learn

Reviewed by skatealexia 19/08/2012

Read less
Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Energy, Respiration & the Environment essays

  1. Marked by a teacher

    Effect of nitrate concentration on the growth of Duckweeds

    5 star(s)

    Also I did not put any of the duckweeds into the wells until I collected enough, as I wanted the experiment to start at the same time to ensure reliability of the all the replicates, as they will be exposed to the same environment.

  2. Marked by a teacher

    Measurments of boby temperature, heart rate and breathing rate

    3 star(s)

    What made this experiment a fair test Before doing any of these experiments we made sure we knew what to do so that it would all be fair and accurate. We made sure we done the same exercise each time for the same time and in the same pace, we

  1. Effect of temperature on the hatching success of the brine shrimps

    responsiveness of the enzymes during the hatching of the egg cyst, there are more collisions so the substrate binds with the enzyme's active site more frequently, thus increasing the rate of reaction of the hatching processes. For this investigation we can see that the "optimum" temperature is 25�C, this means

  2. Describe the concept of homeostasis and the homeostatic mechanisms that regulate heart rate, breathing ...

    Roles of the skin in control of the body temperature- roles of arterioles and sweat glands. Arterioles: When a person has high body temperature the arterioles are widened and because of this blood flows through very easily allowing the blood to go through to all parts of the body

  1. the Effect of Copper Ions on a

    Preliminary Experiment Apparatus * Bacterial amylase solution 0.2M, 100cm3 * Starch solution 0.1M, 100cm3 * Copper sulphate solution 0.1M, 25cm3 * Iodine solution 1.0M, 25cm3 * 3 10cm3 syringes * 9 test tubes (3 for amylase, 3 for starch and 3 for the CuSO4 concentrations)

  2. What Is The Effect Of Caffeine Of The Heart Rate Of Daphnia?

    the microscope and proceed to record the number of beats of the heart for 30 seconds then, double the number for a the amount per minute. Repeat this step 2 more times. Results: CAFFEINE SOLUTION HEARTRATE OF DAPHNIA ? BEATS /MINUTE 1 2 3 AVERAGE HEART RATE / MINUTE 0

  1. Effect of caffeine on heart rate on Daphina

    Absorb all the excess water with a paper towel. 3. Add a few drops of distilled water along with a few strands of cotton wool into the cavity slide.

  2. Investigation into how Lichen growth is affected as you move further away from a ...

    Dictionary of the Fungi. (10th Ed.). Wallingford: CABI. ISBN 978-0-85199-826-8. 8. Knowles M.C. (1929). "Lichens of Ireland". Proceedings of the Royal Irish Academy 38: 1?32. 9. Purvis, O.W., Coppins, B.J., Hawksworth, D.L., James, P.W. and Moore, D.M. (Editors) 1992.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work