• 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

Investigate which surface of a leaf loses more water by transpiration.

Extracts from this document...

Introduction

PLAN SECTION 1 An investigation into which surface of a leaf transpires more by transpiration. Brief statement of investigation I am going to investigate which surface of a leaf loses more water by transpiration. I will do this by covering certain sides in a layer of Vaseline. The Vaseline will prevent transpiration occurring on that particular side allowing me to see which side transpires more. Risk assessment The number of risks in this assessment is minimal but the following risks will be present: * Any leaves must not be consumed * Extreme care must be taken when handling glass Vaseline pots * Paper clips must be handled with care and must not be uncoiled * All personal property should be tucked away while the experiment is being carried out Independent variable The surface(s) covered by Vaseline i.e. topside or underside. Dependent variable The amount of transpiration that occurs from a particular surface and therefore the amount of weight lost due to transpiration from one particular surface. Number and range of readings I will be making one reading for each leaf after about 20 hours. SECTION 2 Prediction I predict that the underside of the leaf will transpire more. I also predict that the amount of transpiration that occurs from the two leaves with one surface vaselined will be roughly the same as the amount that occurs from the leaf with neither of its side's vaselined. ...read more.

Middle

ANALYSING EVIDENCE SECTION 1 Graphs Section 2 Process data and evidence The first graph shows that leaf 1 had the highest percentage weight loss followed by leaf 4 and then leaf 2 and 3. This supports my prediction that the underside of the leaf will transpire the most because leaf 1 is the leaf with just the underside showing. However, I did expect leaf three, the leaf with none of its surfaces Vaseline to transpire more than leaf 1 so this is an anomalous result. Also, this graph does not support my second prediction that the percentage weight loss of leaves 1 & 2 should roughly add up to the percentage weight loss of leaf 4 as they add up to a significant amount more. This all suggests that leaf 4 is a large anomaly. Section 3 Conclusion based on section 1 & 2 above From my evidence I conclude that more transpiration occurs from the underside of the leaf where the stomata are situated. Relate conclusion to detailed scientific knowledge The reason for my conclusion, similar to that of my first prediction since it proved to be right, is that the underside is covered in stomata pores, making it possible for water to leave the leaf when the pores are open. On the topside however, there are no pores, just a waxy layer instead. ...read more.

Conclusion

would result in the normal side receiving a boost from the wind (leaf 1), upsetting the balance. One may argue that if the unvaselined underside is facing the draught and so transpires extra, this is fair since you would expect it to transpire more anyway but we are not only looking for which side transpires more, we are also looking for particular relationships in the amount of transpiration between the leaves. Another way of curing this apart from putting the leaves in a draught free environment would be to point all of the vaselined sides the same way. All of what I have said here also applies to sunlight, and sources of either temperature or humidity. The only reason that we didn't do all this when we were carrying out our experiment was because we didn't think of it. Also, it may be necessary to revise the time period that I leave the leaves to transpire, because some of the smaller leaves may reach the end of their 'transpiration period' and so the bigger, chunkier leaves will have a larger percentage weight loss because they will continue to transpire for longer. A period of around 6 hours may have been a lot more suitable. Additional evidence Additional evidence such as results obtained by previous groups carrying out this same experiment would have been useful for me to compare my results with and see if they showed similarities. However, I did not have any previous results so I wasn't able to do this. ...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

3 star(s)

***
A sound summary of the investigation but results are not reliable and it lacks a detailed discussion of factors affecting the rate of transpiration. This gives the impression the author is not completely familiar with relevant concepts.

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)

    I decided that a paintbrush and a plastic spoon would be employed to transfer the woodlice. The spoon can collect them whilst the paintbrush can then push them gently from the spoon on to the base of the container. In this way the woodlice will not come to any harm.

  2. An experiment to investigate the water loss from leaves through stomata.

    If no petroleum jelly is put on the leaf then water will escape through the stomata because nothing is preventing the water vapour from escaping. Plan of the experiment In the experiment the independent variables will be the amount of petroleum jelly put on the leaves.

  1. The effect of wind speed on the rate of transpiration.

    I will subtract the weight for 40cm from the previous weight for 20cm and so on till I get to 100cm. I am measuring the loss of mass. Here is what my table of results will look like. Distance (cm)

  2. Does Leaf Surface Area Affect the Rate of Transpiration in a Plant?

    This immediately reduces the rate of transpiration (as well as photosynthesis). If the loss of turgid extends to the rest of the leaf and stem and the plant begins to wilt. Prediction: I think that the rate of transpiration will increase in proportion to the surface area of the leaf.

  1. Determine the Water Potential of Potato tissue.

    The use of tap water was mentioned in the plan. It was impossible to use distilled or deionised water, as this is expensive and there was insufficient supply. Tap water often contains chlorine, fluoride, sulphur, minerals, salts, and heavy metals such as copper, lead and iron.

  2. Determine the water potential of potato tuber cell with the varying affect of solute ...

    When using the balance, we will make sure that the balance is reading zero before you begin and make sure to subtract the weight of the filter paper to figure out the weight of the potato or you will be adding extra weight which will give you the wrong percentage change Preliminary work / Pilot run:)

  1. Investigating the Factors Affecting Respiration in Yeast.

    to do everything exactly as I had been told to on the first day, and how my method says to. 4. The intended temperature was 60oC of course and if you look at the results table you can see that the actual temperatures at the beginning were only two degrees off at the most.

  2. How Does Water Depth Affect Wavespeed?

    This means that the curve on the graph begins to flatten out as the water depth continues to increase. Eventually, it will completely flatten out because there will be a water depth at which the wavespeed reaches its maximum speed and after that it will no longer increase.

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