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

An investigation into the density of 'mock blood'

Extracts from this document...


Chris Ellison An investigation into the density of 'mock blood' Sample A - blood taken from a normal healthy adult male who lives at sea level. Sample B - blood taken from the same male after six months of aerobic exercise. Sample C - blood taken from the same male after training for three months at altitude. Results Time taken for a drop of the sample to fall through 100cm3 of Copper (II) Sulphate Solution. Sample A (Seconds) Sample B (Seconds) Sample C (Seconds) 11.5 12.0 10.0 11.5 13.0 8.0 14.5 12.0 10.0 14.0 12.0 7.5 12.0 13.5 10.0 12.5 14.0 11.0 14.0 16.0 7.0 12.5 12.0 8.5 16.5 14.5 9.5 12.0 11.5 7.5 Mean 13.10 Mean 13.05 Mean 8.5 Now I am going to carry out some statistics on my results to find if they occurred by chance or not. I am going to use the t-test because I need to compare two sets of results that I collected. T-test tables Sample A x x-x (x-x)2 11.5 1.60 2.56 11.5 1.60 2.56 14.5 1.40 1.96 14.0 0.90 0.81 12.0 1.10 1.21 12.5 0.60 0.36 14.0 0.90 0.81 12.5 0.60 0.36 16.5 3.40 11.56 12.0 1.10 1.21 x = 13.10 ? ...read more.


It also means that is a greater than 0.1 chance that it occurred by chance. This makes sense as my research showed me that aerobic exercise only affects the heart and muscles not the density of the blood. Sample A compared with Sample C The P value for this t-test however is very different. The value was P<0.001, this means there is a difference and that this out come was not reached by chance. If you did this test again the same result would occur 99.9% of the time. Training at altitude can change the density of the blood. The kidney keeps a constant check on the oxygen in the blood as part of homeostasis and when they are low because you are at altitude a hormone is released. This hormone tells the bone marrow to produce more red blood cells. The more red blood cells in your blood the more dense it is and this showed up in our tests. Evaluation I believe that the experiment was accurate enough for the results needed to do our coursework. ...read more.


We used a stopwatch operated by us at eye level with the measuring cylinder. The size of the drop could not be measured either which meant we had variations in that too. The size of the drop would affect the surface area and therefore friction acting upon it; this would slow down the droplet. The shape that was usually a doughnut shape could also change. These are all reasons for my results to be anomalous. To counter some of these problems we could use other equipment or methods. We could use a light gate that works by detecting a break in a beam of light caused by a blob of mock blood falling through the solution. This would greatly improve the accuracy of the results, as would having two people to record and time the results. The main sources of error in the experiment were mainly human error in the fact that the person carrying out the experiment controlled the drop size and timing. Most of the time there weren't any problems with our techniques but errors were still made. ...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 Probability & Statistics 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 Probability & Statistics essays

  1. I am going to design and then carry out an experiment to test people's ...

    8 21 0 6 9 12.5 8 22 10 6 11 13 8 23 20 13 15 13.5 8 24 15 16 6 20 8 25 17.5 5 14 10 8 26 8.5 13 11.5 19.5 8 27 9 5 18 11 8 28 9 7 6 8 8 29

  2. Driving test

    There is a steep negative correlation, which indicates that the number of lessons benefits males by a large amount. The equation of the line is y=-0.5013x + 27.099. This gradient means that for every 2 lessons taken the driver will make 1 less mistake. (Reduces mistakes by 0.5013 every lesson)

  1. Throughout this experiment I have decided that I am going to investigate the tensile ...

    This method of measuring the extension of the wire would be much better than measuring it vertically because it would allow a longer sample to be tested therefore allowing us to use bigger numbers, making the data handling and presenting a lot easier.

  2. &amp;quot;The lengths of lines are easier to guess than angles. Also, that year 11's ...

    A curve can then be drawn, and then a box plot can also be drawn. This is a cumulative frequency table to show the year 11 and the year 9 estimates for the length of line 2. These are drawn so I will be able to find the inter-quartile range

  1. Identifying Substances Experiment

    in water Insoluble Soluble Soluble Soluble Soluble 3 Reaction in acid Fizzles and some dissolves None None Turns yellow Fizzles 4 Electronic conductivity Low High High High High Table 1. Physical and chemical properties of the 5 unknown samples. Identification of the 5 unknown samples After I've done experiment and

  2. Reaction Times

    21 20 < r < 25 03 24 25 < r < 30 01 25 I will use a cumulative frequency graph with the inter-quartile range and box-plots. I will use A Cumulative Frequency Graph as I will be able to compare ranges (I.Q.R.), find the median and aid with boxplots to identify outliers and show skewness.

  1. An Investigation Into An Aspect Of Human Variation.

    To do this effectively, the foot length and hand span was clearly defined so that measurements were taken consistently and compared accurately. All measurements were taken using a standard metre long tape measure. Each measurement was recorded to the greatest degree of accuracy possible (nearest millimetre).

  2. Development of Quantitative and Qualitative measures of Human Impact on Wimbledon Common.

    all pairs of the same species (ii) all pairs of mixed species (iii) Combined data. A correlation coefficient is calculated where x represents the log of combined diameter and y the log of the distance of the nearest neighbours. Point Centred Quadrat method. A Point is established at random in the study area.

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