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

How does caffeine affect heart rate?

Extracts from this document...


How does caffeine affect heart rate? Introduction This experiment is to investigate the affect of caffeine on the heart rate. Daphnia The Daphnia also sometimes called a water flea is a genus of Crustaceans that is found abundantly in small bodies of fresh water. Some of these are just large enough to be seen without a microscope in good light. Daphnia belongs to Kingdom Animalia, Phylum Arthropoda, Order Cladocera, Family Daphnidae, Genus Daphnia, and Species Daphnia pulex. It is usually found in fresh water, although there are some that live in salty water. It is an important link in the aquatic food chain. Daphnia has a small and semi-transparent body, which help one to study the effects of various drugs on the heart. It is a type of small crustacean and is generally 0.2 to 3.0 mm long. Apparatus We need * Culture of daphnia * Cavity slides * Standard glass ware (beaker) * Dropping pipettes * Filter paper * Cotton wool * Microscope Planning 1. In pairs, set microscope, stop clock, and the slide. ...read more.


Then we are made to exchange the slides. Random errors can occur by not following the standard procedure also carelessness can produce random errors as well. Implementing the plan 1. Set up microscope in pairs. 2. Set up the cavity slides 3. Take one slide and add 2-3 drops of ice water in it, this will later act as the heat sink. 4. Then place another on the top, facing the converging side up. 5. Using pipette, transfer a large daphnia from the pond water to the cavity slide. 6. Providing enough water will help to have sufficient amount of oxygen to the daphnia 7. Place few straits of cotton wool on the cavity slide to prevent the movement of the flea. 8. View the water flea under a low power compound microscope 9. Focus on its heart which can be seen through its translucent body 10. Use a stop watch to record the number of heart beats per minute 11. One person count beats while other tells time 12. Tap a pencil on a paper and count up the pencil marks at the end of the time period 13. ...read more.


124 122 138 147 150 136 Average 140 141 144 147 154 145 Caffeine 141 146 167 180 162 157 On daphnia 142 152 147 150 164 157 142 183 202 176 142 131 168 150 154 150 148 150 150 170 147 159 162 161 Average 142 155 172 146 162 160 Graph Validity /Reliability of the Results I think the results I got are reliable, because this activity is done 5 times by each student and there were 6 groups to do this so this is repeated 10 times and taken the average. In order to make the results valid I have controlled the variables that I think would have made an effect .the graph shows a trend that caffeine has an effect on heart rate. Summary It is clear from the results table and the graph that the heart rate of daphnia is high for those which was on caffeine. So I conclude that caffeine has a positive effect on heart rate .it can increase the heart rate. The results table shows that, as the time increases the heart rate also increases, this is because of the stress that it experiences. ...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

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

    How caffeine affects Daphnia heartbeat?

    4 star(s)

    Also when measuring the daphnia's heart beat we are counting for 15 seconds then multiplying the result by four to make it a result for 1 minute. Results Daphnia practical results Group Concentration of Caffeine Beats per minute 1 0 120 0.1 140 0.5 168 2 0 109 0.1 120

  2. In this experiment I aim to find out if caffeine has an effect on ...

    well-being of the living organisms involved in the experiment should be taken care of, so that they do not suffer for the experiment or at least their sufferings are minimized.

  1. Investigating the effect of caffeine on the heart rate of Daphnia

    Hazard Likely hood Severity Total risk Masses falling off and hitting a student 4 3 12 Cutting yourself when chopping the celery 3 3 9 (0-5 = Safe experiment, 5-10 = Take Care, 10-15 = Teacher controlled, 15+ = Not safe)

  2. The aim of this experiment is to research on the effect caffeine has on ...

    slowly increase when differing amounts of caffeine solution is administered to it. If it is tested on humans or animals, it may be proven to be unethical. However, if a greater amount of the caffeine solution (1%) is added to Daphnia it may cause paralysis.

  1. Field trip report Mangrove ecosystem

    3 to 4cm board, it has salt glands to remove excess salt absorbed, thus can survive in seawater. Flowers: White and small, appear in dense clusters, with 5 partly fused petals, pentamerous in shape, pointed in bud with 1 to 2 cm long.

  2. the effect of bile concentration on the activity of the enzyme lipase during the ...

    Furthermore because the graph begins to plateau, we can conclude that as you increase the bile salt concentration eventually it will have no effect on the enzyme activity as the enzyme can only help catalyse the breakdown of a set amount of fat molecules.

  1. Weed study. Dandelions - descrption and characteristics. Investigation to dandelion distribution.

    In case I come in contact with it. These are the basic risks and hazards for my investigation. Results Data collected. Lower Lawn: Quadrat number Air Temperature (?C) (1dp) Soil Depth (mm) Frequency of dandelion PH level (2dp) Light Intensity (lux) 1 15.0 91 3 7.91 6480 2 15.0 141 9 7.86 6600 3 15.0 166 10 7.82

  2. out how different concentrations of the enzyme pectinase affect the degradation of the substrate ...

    to see whether any apple juice may get produced without the presence of pectinase. Then I will use the concentrations 50%, 75% and 100% of pectinase in order to see the change in the volume of apple juice produced as the percentage of pectinase increases, and hence we will be

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