Introduction: (Total: 10 pts)
1. Transpiration is critical for plant physiology. In your own words, what is transpiration, and why is this important in plants? (2 pts)
Transpiration is the process of liquid transforming into the gas phase of water when the stomata open. It is very important for plants; it allows plants to pull up water from the roots to support photosynthesis. This process also takes up mineral from the root to supply the biosynthesis of the leaves in addition to cooling the leaves.
2. Plants can respond to abiotic factors and alter their transpiration accordingly. How do plants regulate transpiration (cite primary literature here!)? (3 pts)
Transpiration occurs through the opening or closing of the stomata, which is regulating by the concentration level of carbon dioxide gas and the concentration of water vapor in the atmosphere (Sadava 2011).
3. Many abiotic factors can affect transpiration rate. List these factors, and underline the ones that you selected to test. What have other researchers previously found out about the three factors that you selected? (cite scientific primary literature here!) (3 pts)
Many abiotic factors such as wind, heat, light, humidity, sealed stomata, leaf surface area can affect the transpiration rate.
Jarvis (1964) found the transpiration rates for Quercus petraea seedlings were higher in unshaded treatments than shaded treatments.
The transpiration rate of mushrooms was reduced by 87% through increasing the humidity of the storage container from 76% to 96% (Mahajan et. al 2007).
Leave surface area
Parker (1948) found the transpiration rates of loblolly pine and red cedar to increase directly through increased ratio of root surface to leaf surface area.
In the laboratory, you were asked to determine three hypotheses (predictions) for three factors that you selected to test. Re-write your three hypotheses and explain the rationale...