Stomatal Density Lab Report Sample

Stomatal Density Report The purpose of our first experiment was to learn about the importance of stomata physiology for plants, and test a hypothesis regarding stomatal density. Stomata are vital to plant function because they let the plant take in carbon dioxide from the atmosphere and release water vapor. Stomata are surrounded by two guard cells that help them open and close in response to their environment. We were given the choice to test either the null hypothesis or the alternate hypothesis. The null hypothesis proposed that there is no difference between stomatal density of a young and mature hibiscus leaf. Conversely, the alternate hypothesis hypothesized that there is a difference between stomatal densities in young and mature hibiscus leaves. I chose to test the alternate hypothesis because I thought a young plant with a higher density of stomata would have access to more resources, allowing it to grow quickly. After doing some research on the topic I learned that the “evolution of stomatal size is driven by pressure on the anatomical maximum stomatal conductance which determines the operational range of gas exchange.” (de Boer, Hugo …show more content…
The average stomatal density that I calculated for the young leaf was 110 stomata/mm2. The average stomatal density that I calculated for the mature leaf was 98.75 stomata/mm2. However, while reviewing the statistics gathered from two class periods it appears that young leaves do not have a higher stomatal density compared to mature leaves, it appears that the reverse is true. The average stomatal density for the mature leaves was 75 mm2, compared to the average stomatal density for the young leaves which equaled 61.25 mm2. Therefore, we cannot reject the null hypothesis that there is no significant difference between stomatal density for young and mature hibiscus leaves (t=-1.019, N=10,