We were unable to accept our hypothesis that monocots had the greatest stomatal frequency and smallest stomata size based on the results gathered in Table 2. Table 2 also shows that there is variation amongst different species and there isn’t always a proportional distribution of stomata. We did however observe a negative correlation between stomatal frequency and stomata size which previous research proves is expected (Doheny-Adams T. et al., 2012). We found that Ginkgo biloba smallest stomata size and lowest stomatal density, which supports a negative correlation. The stomata were only visible on the abaxial side. Reasoning for this could have been because the cuticle was too thick to see stomata on the adaxial side or because stomata are not present in species like the Polypods due to flooding. In the third experiment, we were able to accept our hypothesis that Platanus racemosa would have a smaller secondary vein length per area value than Rhus integrifolia (Figures 1 and 2). We saw that Rhus integrifolia, the drought tolerant species, was smaller in leaf size and had third order major veins because having a larger leaf would cause the plant to lose more water due to transpiration. By having a small leaf, the surface area is decreased and energy can be put into the roots in order to find water instead of keeping a large leaf alive. The Platanus racemosa leaf was bigger in size and also had third order major veins. The fourth order veins seen on the leaf (Figure 4) is considered to be a minor vein. The leaf of Platanus racemosa is big because it does not live in drought conditions. This means that the plant gets enough water in order to maintain its bigger leaf size. Having a bigger leaf size increases its chances of capturing light and carbon dioxide in order to go through photosynthesis. For further research into understanding transpirational responses to enviornemntal changes, performing a multi-variable test may prove more useful for understanding conditions that actually occur in nature. For example the effects of hot and dry weather vs cold windy weather.
REFERENCES Boyer, J. S., S. C. Wong, and G. D. Farquhar . "CO2 and Water Vapor Exchange across Leaf Cuticle (Epidermis) at Various Water Potentials." Plant Physiology 114.1 (1997): 185-91. Web. Doheny-Adams, T., L. Hunt, P. J. Franks, D. J. Beerling, and J. E. Gray . "Genetic manipulation of stomatal density influences stomatal size, plant growth and tolerance to restricted water supply across a growth carbon dioxide gradient." Philosophical Transactions of the Royal Society B: Biological Sciences 367.1588 (2012): 547-55. The Royal Society Publishing . Web. Domingos, Michael . "The Crucial Role of Stomata in Plant Transpiration and Photosynthesis." HubPages . HubPages, 29 Apr. 2012. Web. 10 May 2017.
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