• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
Page
  1. 1
    1
  2. 2
    2
  3. 3
    3
  4. 4
    4
  5. 5
    5
  6. 6
    6
  7. 7
    7
  8. 8
    8
  9. 9
    9
  10. 10
    10
  11. 11
    11

Investigate the effect of huddling on heat loss.

Extracts from this document...

Introduction

Huddle investigation PLANNING A Aim: to investigate the effect of huddling on heat loss Hypotheses: 1. That the larger the huddle, the smaller the amount of heat lost. That is, an organism (test tube) on its own will lose more heat than if it were huddled in a group. In an experiment using test tubes, this will be supported by data which shows that a test tube by itself will lose more heat in the same amount of time than if it were in a huddle. 2. The temperature loss should decrease proportionally as the size of the huddle grows. 3. Also, the organism (test tube) in the centre of the huddle will lose less heat than an organism or test tube on the outside of the huddle. The reasoning behind this hypothesis is that as the huddle group grows in size, the amount of exposed 'surface area' will be reduced per test tube. Although in practice not every test tube is exposed, theoretically, this is a way of comparing huddles. Also, in a huddle of many organisms, or test tubes, if there is a centre test tube which is not 'exposed', it will be warmer than those on the periphery of the huddle. This hypothesis can be supported by data collected in the experiment by measuring the temperature of the centre of the huddle and the periphery of the huddle. The centre will be warmer because it has no surface area exposed to the outside. Huddling is a behavioural adaptation to the cold climate. 'Huddling' (in the case of penguins) is when a group of penguins stand closely together, nestling, in an attempt to reduce heat loss collectively as a group. This idea is effective because as a group, the penguins have lesser surface area exposed to the cold per penguin. Thousands of penguins have been seen in the Antarctic nestling together. ...read more.

Middle

of the 10 Test Tube Huddle Trial 1 Trial 2 Trial 3 Trial 4 Time (mins) Inner TT Outer TT Inner TT Outer TT Inner TT Outer TT Inner TT Outer TT 0 46.0 44.0 46.0 44.0 49.0 48.0 48.0 46.0 1 45.5 43.0 45.0 44.0 49.0 47.0 48.0 45.0 2 45.0 43.0 45.0 44.0 48.0 46.0 47.0 44.0 3 45.0 42.0 44.0 42.0 47.5 45.5 46.5 43.0 4 44.0 41.0 44.0 42.0 47.0 45.0 46.5 42.5 5 43.0 40.5 44.0 41.5 46.0 44.0 46.0 41.5 6 42.0 39.5 43.0 40.5 45.5 43.0 46.0 41.0 Physical Measurements of the huddle Table showing the physical measurements of the huddle and the test tubes 1-test tube 7-test tube huddle 10-test tube huddle Circumference (cm) 6.9 24.5 31.6 Length of test tube (cm) 15.0 DATA PROCESSING AND PRESENTATION Change in temperature in the experiments Table showing the change in temperature (Initial temperature - Final temperature) Temperature (�C) Trial 1 Trial 2 Trial 3 Trial 4 Average 1-test tube huddle 6.0 5.5 6.0 8.0 6.375 7 test-tube huddle - INNER test tube 2.5 1.5 2.0 3.0 2.250 7 test tube huddle - OUTER test tube 3.0 3.5 4.0 5.0 3.875 10 test-tube huddle - INNER test tube 4.0 3.0 3.5 2.0 3.125 10 test tube huddle - OUTER test tube 4.5 3.5 5.0 5.0 4.500 The variations in starting temperature in this case were ignored, as it was the initial temperature minus the final temperature calculated, thus the change was measured. It can be seen that the average change in the 1-test tube experiments were vastly different to those obtained in the other experiments. However this figure may be distorted by the result of Trial 4. If we look at the individual results from Trials 1 to 3, they are comparable with the results from the outer test tubes of the 10-test tube huddle. In this way, they do not look so atypical. ...read more.

Conclusion

We have to take note of the fact that glass absorbs and retains heat, and so the 'heat loss' we are attempting to measure may not be completely accurate. However, if we draw parallels between the test tube and skin of the animal, this may be accurate because the animal would retain the heat in its fur/feathers, thus not all the heat would be lost to the external environment. The heat loss in the water can be paralleled with the core temperature of the animal. I did not take into account the area exposed at the top of the test tubes, or at the bottom of the test tube because these would have been too difficult to measure. The meniscus of the water would prove difficult to measure, as would the curve of the bottom of the test tube. Furthermore, heat lost from the top would not be through glass (there is on glass at the top of the test tube). The bottom of the test tube is also thicker than the sides. Thus, heat lost from both these gaps would not be the same as heat lost from the sides. In order to keep the experiment consistent, these were ignored as part of the calculation for 'surface area'. Time restrictions must also be considered. Although the time the temperatures were measured over was fairly small (6 minutes), there were still palpable differences between the experiments, and the hypotheses could be supported with the data collected. The differences were not so small it was difficult to establish whether or not there was a pattern. However if the experiment was conducted over an even longer period of time (perhaps 10 minutes), the patterns may be even more distinct. Perhaps in the long run the 10-huddle may have performed better than the 7-huddle in heat loss. The temperature could also only be measured to 1 decimal place, but my partner and I decided to round up to the nearest half or whole number. This way, interpretation is clearer and reading the thermometer can be done with ease. ...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 Green Plants as Organisms 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 teacher thought of this essay

5 star(s)

*****
A high level of attention to detail is shown throughout this account. A clear understanding of concepts is evident. There are few errors.

Marked by teacher Adam Roberts 18/07/2013

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 Green Plants as Organisms essays

  1. Peer reviewed

    An Investigation into the Effects that Different Light Intensities have on the Speed of ...

    5 star(s)

    A species, which shows taxis, can orient the direction of their movement with respect to the source of an external stimulus whilst kinesis is a steady-state dependence of the movement velocity on the stimulus intensity.iii Thus it is clear that kinesis will be the important response in my investigation as I am not concerned with the stimulus direction.

  2. Use the method of mixtures to find out the specific heat capacity of a ...

    First off, the apparatus used allowed us only to measure the initial temperature of the brass by reading the temperature of the water it was in, making it in actual fact not even a measurement of the brass' temperature. Following that it had to be transferred into a beaker of water at room temperature.

  1. Effect of Surface Area on Transpiration

    There is little change in water uptake between 0 and 4 leaves. This is due to the more mature leaves being near the bottom of the plant. These leaves would have thicker cuticles which would cause less transpiration. When the leaves where removed, they were removed from the top of

  2. An Investigation into Water Loss from Plants.

    The guard cells are forced to become turgid and open when the light intensity is high as this is when photosynthesis starts. This means that Carbon Dioxide is used up during photosynthesis increasing the pH of the cells which activates an enzyme which converts starch to glucose.

  1. The relationship between flow rate and temperature difference

    * My setup could not easily be changed to adjust any factors because it was simply the back of an old freezer and it came like that and could not be altered without damage being done. * There was way of keeping the temperature constant because there was no way of regulating the heat given out by the light bulb.

  2. What is the effect on the rate of respiration of yeast cells with glucose ...

    timers A gas syringe A delivery tube with rubber bungs tightly fitted at the ends joined to the gas syringe A thermometer A clamp stand An electrical water bath A kettle for boiling water A 250ml beaker The entire investigation was carried out at 30�C, 40�C, 50�C and 60�C.

  1. Find out the effect of temperature on the bounciness of a ping-pong ball.

    As soon as the ball is thrown and looks at how high it bounces back. 4. Heat the water in the beaker again until 45 degrees Celsius. Then leave it for 5 minutes and put the ball back in. Then repeat step 3 again, and note the result as try 2.

  2. Describe a time when you felt disappointed or let down

    "What?!" they all cried "What!?? I'm getting three bags of water balloons and a bucket, least you lot can do is bring plenty of water!" They agreed and we all set off home to prepare. I chose the quickest route home via the endangered art of fence hopping, well it cut

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