Methods For the three experiments we followed the lab procedures as stated in

Methods for the three experiments we followed the lab

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Methods: For the three experiments, we followed the lab procedures as stated in the provided lab manual (Sack 2016). For experiment one, we set up a photometer using Heteromeles arbutifolia (Rosaceae) to examine water loss per minute (mL H 2 O per minute). We first tested the full sunlight environmental condition by leaving the plant out in the sun for 15 minutes while marking the water level every five minutes. We then tested cool wind blowing over the leaves using a hair dryer on cold setting similarly. Finally, we tested hot wind blowing over the leaves similarly. We tested this last because the hot air might potentially damage the leaves. For experiment two, we gathered leaves of a tree fern (fern), Ginkgo biloba (gymnosperm), wild ginger (monocot), and Macadamia integrifolia (dicot). For experiment three, Ficus sp. was used for the dry habitat species and Platanus racemosa was used for the moist habitat species.
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Results: Table 1 shows the average transpiration rates for the different environmental conditions conducted in experiment one. The transpiration rate for being outside in full sunlight was 128% relative to the control. The transpiration rate for blow-drying in cool air was 244% relative to the control. The transpiration rate for blow-drying in hot air was 256% relative to the control. For experiment two, the tree fern had adaxial stomatal density of 5.8 stomata per mm 2 and stomata length of 0.08 mm. The tree fern had abaxial stomatal density of 169.5 stomata per mm 2 and stomata length of 0.12 mm. The Ginkgo biloba had no adaxial stomata and we also did not observe any abaxial stomata. The wild ginger had no adaxial stomata. The wild ginger had abaxial stomatal density of 149.1 stomata per mm 2 and stomata length of 0.10 mm. The Macadamia integrifolia had adaxial stomatal density of 4.1 stomata per mm 2 and stomata length of 0.08 mm. The Macadamia integrifolia had abaxial stomatal density of 5.1 stomata per mm 2 and stomata length of 0.09 mm. For experiment three, the small Ficus leaf had an area of 10 cm 2 and a total second order vein length of 6 cm. The large Ficus leaf had an area of 19 cm 2 and a total second order vein length of 10.9 cm. The small Platanus racemosa leaf had an area of 40 cm 2 and a total second order vein length of 8.7 cm. The large Platanus racemosa leaf had an area of 307 cm 2 and a total second order vein length of 7.4 cm. Discussion: Our hypothesis for experiment one was supported. Transpiration rate for blowing hot air was higher than the other test conditions as seen in Table 1. Transpiration rate was lowest in the sunlight experimental condition, with the control having an even lower transpiration rate than that. Transpiration from the leaf depends on a few driving forces: relative humidity, temperature, the amount of water in the soil, light, and wind. When there is wind, the boundary layer is disturbed, which lowers the plant’s resistance to transpiration. Faster wind speed causes a smaller boundary layer, which causes a higher the rate of transpiration. Environmental light,
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  • Spring '18
  • LAWREN SACK
  • transpiration rate, adaxial stomata, stomata length

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