Transpiration
Janaeza Naejan E. Tiongco July 10, 2013
AB-2L Prof. Marilyn Combalicer
Exercise 3
TRANSPIRATION
I. Result and Discussion
1. Effect of the Environment Factors on the Rate of Transpiration
The quantitative rate of transpiration of the branch of papua dilaw was determined using the potometer. The distance travelled by the bubble in the capillary per unit of time was observed under different treatments: a. in front of a fan, b. exposed to light, c. fan and light, d. no treatment.
Table 1. The transpiration rate of the branch of papua dilaw when exposed to different treatments
Treatments
TRANSPIRATION RATE (cm/sec) Reading 1 Reading 2 Average
a. Fan
7.33x10-3
5.33x10-3
6.33x10-3
b. Light
6.67x10-3
5.33x10-3
6.0 x10-3
c. fan and light
8.0x10-3
6.67x10-3
7.33 x10-3
d. no treatment
5.67x10-3
5.33x10-3
5.5 x10-3
Given the data above, it can be simplified that the treatment with the use of both fan and light yielded the highest rate of transpiration. In contrast, the control treatment showed the lowest rate of transpiration. Light plays an important role in the rate of transpiration. The stoma of the plant opens when exposed to light which permits the transpiration to occur. Oppositely, when there is the absence of light, transpiration ceases (Bold, 1997). The effects of other environmental factors are, therefore, dependent upon the presence of light. Wind affects the rate of transpiration because the water vapor in the leaf area is being dispersed by the wind; as the vapor is being dispersed, the rate of transpiration will increase (Levitt, 1974).
2. Effect of Leaf Characteristics on the Rate of Transpiration
The weight of the leaves of kaimito, mahogany, avocado, kaatoang bangkal, yemane, and mangium were determined initially and after one hour of exposure to the electric fan. The area of each leaf was also determined using the weight method. Finally, the
AB-2L Prof. Marilyn Combalicer
Exercise 3
TRANSPIRATION
I. Result and Discussion
1. Effect of the Environment Factors on the Rate of Transpiration
The quantitative rate of transpiration of the branch of papua dilaw was determined using the potometer. The distance travelled by the bubble in the capillary per unit of time was observed under different treatments: a. in front of a fan, b. exposed to light, c. fan and light, d. no treatment.
Table 1. The transpiration rate of the branch of papua dilaw when exposed to different treatments
Treatments
TRANSPIRATION RATE (cm/sec) Reading 1 Reading 2 Average
a. Fan
7.33x10-3
5.33x10-3
6.33x10-3
b. Light
6.67x10-3
5.33x10-3
6.0 x10-3
c. fan and light
8.0x10-3
6.67x10-3
7.33 x10-3
d. no treatment
5.67x10-3
5.33x10-3
5.5 x10-3
Given the data above, it can be simplified that the treatment with the use of both fan and light yielded the highest rate of transpiration. In contrast, the control treatment showed the lowest rate of transpiration. Light plays an important role in the rate of transpiration. The stoma of the plant opens when exposed to light which permits the transpiration to occur. Oppositely, when there is the absence of light, transpiration ceases (Bold, 1997). The effects of other environmental factors are, therefore, dependent upon the presence of light. Wind affects the rate of transpiration because the water vapor in the leaf area is being dispersed by the wind; as the vapor is being dispersed, the rate of transpiration will increase (Levitt, 1974).
2. Effect of Leaf Characteristics on the Rate of Transpiration
The weight of the leaves of kaimito, mahogany, avocado, kaatoang bangkal, yemane, and mangium were determined initially and after one hour of exposure to the electric fan. The area of each leaf was also determined using the weight method. Finally, the
References: BOLD, H.C. 1997. The Plant Kingdom. 4th Ed. Prentice-Hall, Inc., Eaglewood Cliffs, New Jersey. 560 pp. DEVLIN, R.M., 1969. Plant Physiology. 2nd Ed. Van Nostrand Reinhold, New York. 446 pp. LEVITT, J