Our world is filled with beautiful plants of all different colours. Green is clearly the most prominent colour, and we know that this is due to the presence of chlorophyll. We have also learnt that photosynthesis is a vital process that occurs in order to create glucose and oxygen, by transforming carbon dioxide and water in the presence of light energy. Chlorophyll is vital for this process due to the fact that the light energy which allows for this process to occur is trapped in the chlorophyll molecule. These molecules are situated in the chloroplasts in the mesophyll layer of leaves, but most prominently in the palisade mesophyll which is the main photosynthesising tissue. My interest was sparked when I started to think about the role this so called vital chlorophyll plays and whether it is really necessary for photosynthesis to occur to occur in plants. While thinking about this I noticed that chlorophyll leads to the green colour in plants as green is reflected by the chloroplast cells and red and blue absorbed, therefore plants which are green and white obviously will not have chlorophyll in the parts which are white, as these parts lack the green colour, meaning that photosynthesis is not supposed to occur in these areas. It is also vital to remember that leaves which are fully red still do photosynthesise but the green pigment is just masked by carotenoids, which is why only variegated leaves may be used. The most basic way to actually test this is to look along the lines of leaves which are variegated, meaning they are white and green.
Aim - In this investigation I would like to test whether chlorophyll is necessary for photosynthesis to occur, by testing for the presence of starch in a photosynthesising variegated leaf of colours white and green.
Hypothesis – Chlorophyll is necessary for photosynthesis to occur as the presence of starch (a form of glucose, a product of photosynthesis) will be negative for the white parts of a variegated photosynthesising leaf.
Review of Literature
Article one – Why is chlorophyll necessary for photosynthesis?
Chlorophyll is said to be vital for photosynthesis as it captures light energy, which acts as a catalyst, from the sun to produce glucose, as one of the end products. Chlorophyll itself absorbs light from the red and blue parts of the light spectrum and reflects green, which is why plants appear green. This chlorophyll is found in chloroplasts in the mesophyll layer of the leaf, and allows for the chemical reaction to take place, which involves the transformation of carbon dioxide and water into glucose and oxygen, with the chlorophyll providing the energy for this to take place
Analysis – The quality of this article was of quite a high standard as it gave information which links in with what we have been taught. Along the lines of reliability, there is a bit of questioning as there is no mention of the profession of the author of the page. The article has been updated quite...