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

An Experiment to investigate a factor affecting the rate of Transpiration From a Shoot of Privet (Ligustrum ovale).

Extracts from this document...

Introduction

An Experiment to investigate a factor affecting the rate of Transpiration From a Shoot of Privet (Ligustrum ovale) Introduction; Transpiration is the act or process of evaporation of water through the stomata (opened and closed by guard cells) underneath a plant's leaf. This water comes from the process of photosynthesis because not all the water, which is taken up by the roots by osmosis, actually makes it into the process of photosynthesis. This is because the plant could either be in the dark, or it has more water than is necessary in its leaves. Transpiration is a process that the plant does not want to take place, but it happens because of the need for Carbon Dioxide. The only way that a gas could get into a leaf is through gaps in the outer cuticle. These gaps, also known as stomata, also let the water out as transpiration. Water is near the stomata because this is the 'spongy' area of a leaf so this is where the 'wet cells' are to store the water for photosynthesis. Plants control the water loss through these stomata by being able to close them up. ...read more.

Middle

Key Factors; There are many key factors that affect the rate of transpiration including temperature and the amount of surface area on the plant. Throughout my experiment I will have to keep these factors constant to make this experiment fair. I will keep the temperature constant by measuring it and either opening or shutting the windows or using other means of raising or lowering the temperature. The wind is the factor that I will vary throughout my experiment. I will be using a fan that I can set to many different speeds and also I could move it closer and further away from the plant. Preliminary work; Before a finally set up my experiment (and apparatus shown below) and recorded the results for the graph I completed some preliminary work in which I found out some glitches to look out for. Firstly I found that it was very hard to have only water in the tube and no air bubbles, because if there are any bubbles in the tube then the area of uptake for the plant is greatly decreased and therefore less water would be taken up in a specific time. ...read more.

Conclusion

When the bubble moves along as far as I want it to then I will use the water reservoir to push the bubble back into its original position to repeat the experiment again. I am doing this again because then I will receive more accurate results for my graphs. For this experiment the wind speed is the independent variable so that I can measure the rate of transpiration. But it will actually measure the rate of water uptake, which is almost 99% due to transpiration. The temperature is a variable, which I will control by closing the windows and doing the experiments at the same time of day. The last variable is light, which I will keep constant by shutting the blinds and only having the light from the room lights. Lastly I will soak the plants' stem in water before each experiment because then this will prove that the water taken up by the plant is only transpiration and not for storage in the stem and the leaves. I will then place my results on a graph of water uptake against time. I am hoping that I will receive a graph like to one I drew above. Joshua Tucker 1 ...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

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. Factors Affecting Infiltration Rates

    This was due to the soil, not having any water in it. The soil was quick to suck up the water poured on it. Any soil that is heated up by the sun is left dry and is very quick to tae in water when it rains.

  2. How temperature affects the rate of photosynthesis.

    For e.g. a boiling test tube has a thicker wall and therefore factors like heat would have less affect on the solution inside it. Similarly a solution in a normal test tube with thin walls would be more prone to be affected by heat than a solution in a boiling test tube.

  1. Three separate experiments which are to be carried out to investigate a plant's unique ...

    In the preliminary experiment, we didn't take down results, but made a note of how much water was taken up by the roots (and therefore how much water was lost through the leaves by evaporation). We set our potometers up in several different locations (and therefore different circumstances)

  2. The investigation is aiming to look at transpiration.

    The attraction is called cohesion. They are also attracted to the lignin in the walls of the xylem vessels; this attraction is called adhesion. Cohesion and adhesion help to keep water in a xylem vessel moving in a continuous column.

  1. Factors affecting the rate of transpiration

    From here water vapour diffuses through the stomata, from a high water potential inside the leaf to a much lower one outside the leaf. In dicotyledons, stomata are usually confined to, or are more numerous in, the lower epidermis. Stomata are pores in the epidermis through which gaseous exchange takes place.

  2. Investigation Into The Rate of Water Uptake By Transpiration.

    Plants showing xeromorphic adaptations usually have reduced numbers of stomata. In dicotyledonous plants, the lower leaf surface usually possesses more stomata than the upper surface. In order to make this a fair experiment, the following precautions need to be taken.

  1. Design and Carry out an investigation to see what effect light intensity has on ...

    Time in (secs) The rate of transpiration will be calculated by Rate = Distance traveled (mm) Time (seconds) This will result in the following graph Rate of Transpiration Light intensity (Lux) Within this planning section the accuracy and validity of the data has been discussed, and will now be further

  2. Investigate factors affecting rate of transpiration in a leafy shoot.

    Finishing Mass (g) Loss of Water/per unit mass (ml/g) Dry 80mm 75mm 5mm 1.57 1.94 2.58 Warm 80mm 50mm 30mm 1.25 1.19 7N25.21 Windy 80mm 58mm 22m 1.36 1.45 15.17 Controlled 80mm 55mm 25mm 1.75 2.15 11.63 Conclusions and Analysis: I predicted that the test-tube labelled warm would show the greatest decrease in water level followed by the one labelled dry.

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