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

Daphnia Pulex

Extracts from this document...


Background Information: Ecologists have noticed that the fish in a local river have started to die. Some have suggested that this be because of the pollution from a nearby brewery, which is disrupting the food chain. It is thought that the pollution could influence the heart rate of small invertebrates such as a Daphnia pulex, which will eventually die. Scientific Knowledge that alcohol is a depressant, which slows down the heart rate. The brain is the first organ to be affected by alcohol, because it has many blood vessels. It slows your thinking, affects your judgement, and dulls your senses. As more alcohol is absorbed into the blood stream, the cerebellum and medulla are affected. The co-ordination, balance, reaction time, and then vital body functions such as the heartbeat, breathing rate, and digestion are affected. If you continue drinking alcohol at this point the brain's functioning can slow enough to result in unconsciousness and even death. ...read more.


I am going to be using different amounts of concentration always using 100ml of solution I will be doing volumes of: - 0.5%, 1%, 1.5%, 2%, 2.5% and 3% So for 3% volume to make a total of 100ml I would use 3ml of ethanol and 97ml of distilled water I am going to repeat the experiment for each concentration 5 times so I can get an average set of results, which may be more reliable. I am going to leave the Daphnia Pulex's in the solution for 1 minute. I will then transfer one Daphnia with a pipette on to a dimple slide and cover gently with a slide cover so not to squash the Daphnia Pulex. When it is under the microscope I will measure its heart rate for a minute by timing it for a minute with the stopwatch and dotting on a piece of paper every time it heart beats After I have done this I will count the dots and record the data in my results table. ...read more.


Safe Test To ensure my test is as safe as possible I will have to do these things so I do not cause an accident while doing the experiment. * Wear safety goggles at all times. * Move bags, coats and stools right out of the way so that you do not trip over any of them or so that it can not cause an accident. * Make sure you know exactly what you are doing in the experiment before you start. * Tie longhair back. * Tuck in loose clothes and make sure shoelaces are tied. Results 1 2 3 4 5 Average 0% 250 275 258 289 336 181.6 0.5% 202 176 166 190 198 186.4 1% 110 122 103 123 153 122.2 1.5% 162 178 150 103 120 142.6 2% 139 182 139 144 127 146.2 2.5% 144 137 149 118 138 137.2 3% 150 74 44 76 64 81.6 Samantha Bellamy :) Biology Coursework :) Mr Harwood ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Humans as Organisms 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 GCSE Humans as Organisms essays

  1. Marked by a teacher

    Is the MMR vaccination safe?

    5 star(s)

    1 in 8000 (under 2) 0 Death 1 in 2500 0 However, the risks of the side effects of the actually diseases are far greater than the risk of the child suffering from the effects of the immunisation. This table, from the National Health Service (NHS), shows the chances of

  2. Should you vaccinate using the HPV vaccine?

    There is no vaccination for men as of yet but scientists are working on creating one. The vaccine is not as important for men as women because penile and anal cancers are rare. Men will often, however, come by the human papillomavirus, the same way as women, and just like

  1. is the mmr vaccination safe?

    Because they are weakened, it means that the diseases wouldn't produce the full effects. And because they aren't infectious, it means that the body wouldn't get harmed by the microbes but the immune system still sees the micro-organism as foreign as 'each cell in your body has a marker to distinguish it as 'self.'(Whole food supplements).

  2. Are Vaccines safe?

    try to ensure to their upmost that the vaccines that they approve are indeed safe for the public and they also collect information about the vaccine including the suspected side effects via the Yellow Card scheme, this shows that they are not ignoring that there are potential side effects and

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