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Submitted By stevehill22
Words 280
Pages 2

Chlorophyll is a substance found in chloroplasts, found in the cells of leaves. They are used to produce glucose which is used as plant food and growing materials (e.g. cellulose).A leaf which is exposed to plenty of light will have sufficient amounts of food and will not need an excessive amount of chlorophyll. This enables the leaf to have a small surface area. It is also necessary for leaves in areas of high light intensity, and thus high temperature, to have small leaves to reduce the amount of transpiration. The heat will cause water to evaporate a lot faster.

Leaves in shaded areas will need a large surface area full of chlorophyll to collect as much sun light as possible; essential for survival. These leaves will also have no threat of excessive transpiration because the temperature in the shaded area will be lower and the humidity probably higher.

Transpiration is the removal (evaporation) of water from a plant through the stomata in the leaves; this water is removed in a cycle due to the active uptake from the roots. Transpiration involves osmosis; which is the diffusion of water from a high concentration to a lower concentration through a partially permeable membrane, until both the concentrations are equally saturated.

All these factors i.e. transpiration and photosynthesis, come together to confirm my hypothesis.

To support my hypothesis further, I did a pilot study in a meadow in which I studied the population of certain plant species in areas of different light intensities. I learned that different plants need different environmental factors to grow well. The leaves in the shade were larger than those in the open…...

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