Felipe Torres, TUT 0104
Assignment 2: Phenotypic Plasticity
1. Data Entry – Yes.
2. a. The large sinuses are an adaptation that increases the photosynthetic area of outer leaves. Leaves that are on the outer portion of the canopy have large sinuses because intense sunlight can penetrate the leaf to a greater depth efficiently. b. The leaves on the interior portion of a tree can still be efficient in conducting photosynthesis because they have a relatively large surface area. Interior leaves can also be efficient in conducting photosynthesis if permitted reasonable light that comes through the sinuses of outer leaves. c. Based on column G, although the difference between the ratio of shade leaves and sun …show more content…
T-value: t* = (x̅ - μ)/(s/√n) = (0.06603248205 – 0)/( 0.1419952328/7) = (0.06603248205)/(0.02028503325) t* = 3.25523163981
c. The null hypothesis for this study states that the mean difference in shape ratio between sun leaves and shade leaves is zero. Since the calculated t-value is greater than the critical value, the null hypothesis in this case is rejected.
d. Yes. There is little difference on the ratio between sun leaves and shade leaves however, the values still shows that it is greater than zero which supports the alternative hypothesis of the study stating that the mean difference in shape ratio between sun leaves and shade leaves is greater than zero.
e. Leaves typically show modifications to the amount of sunlight to which they are exposed. With this being said, it is important to use pairs of leaves drawn from the same tree for easy comparison and analyzation of the difference between the two in terms of their adaptation to …show more content…
The experimental method and the statistical approach that was used to test the hypothesis are appropriate in terms of analyzing the correlation between branch diameter and pollen and seed producing cone sizes across conifer species. A similar paper that helps support the methodologies used in this article titled, “Branching habit and the allocation of reproductive resources in conifers” also used methods like Corner’s rule to analyze conifer’s reproductive structures (ie. whether large-diameter branches bear large cones) and used simple regression models to show the association between branch diameter and cone volume of conifers. This approach is similar to the main paper of study. In both articles, both branch diameter and cone measurements were made to determine whether the variability in conifer branching employ a universal effect on the reproductive structures and allocation of conifers. This similarity between the two article provided the main insight of how cone volume was positively and strongly correlated with branch diameter across conifers in