Is There a Significant Difference in Height of Bracken (Pteridium Aquilinum) from a Light Area and a Dark Area?
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Is there a significant difference in height of Bracken (Pteridium aquilinum) from a light area and a dark area?
Abstract: This investigation was designed to compare the height of Pteridium aquilinum in a light area and a dark area of Rushy Plains, Epping Forest and to establish if light intensity does have an effect on the growth of Pteridium aquilinum, commonly known as Bracken. From my research it was clear that the height of Bracken is affected by abiotic factors, other than light intensity, such as: soil moisture, soil temperature, air temperature and soil pH so I had to control these factors. I carried out preliminary experiments to find a suitable site where all these factors where constant. For my actual investigation I measure…show more content… Picture 2
The diagram above shows the two stages of photosynthesis. As you can see, light is a key component as it start the light-dependent reactions which produces ATP and NADPH, which is needed in the light-independent reactions to make glucose. So without light, there is no ATP and NADPH produced and thus no glucose produced, therefore the food chain cannot be started. Glucose is also needed to make DNA and hormones for plant growth, it is also require during plant respiration. So it can be established the light is vital for plant growth and it affects the height of plants indefinitely.
Photoperiodism is the effect of the relative lengths of light and dark periods on plant growth. This occurs when photoreceptor proteins e.g phytochromes are produced by plants in response to light intensity or the absence of light. This in effect affects the height of plants. 
Phototropism is the growth of a plant in the direction of its light source. Phototropism occurs due to a hormone called auxin which is produced at shoot tips. Auxin influences cell division, if there is light on one side then the dark side will receive more auxin and therefore more cell division will occur on that side, which will force the plant to bend towards the light therefore affecting the height of the