In Procedure 2, we also found that the large leaf size against length per area have a values of 3.84 cm − 1 , 4.3 cm − 1 , 4.13 cm − 1 , 2.56 cm − 1 against the leaf size of 55.53 cm 2 , 54.56 cm 2 , 53.21 cm 2 and 51.57 cm 2 . The values for small leaf length per area are 1.95 cm − 1 , 1.78 cm − 1 , 1.7 cm − 1 , and 2.56 cm − 1 . Meanwhile, the values of total small leaf size are 19.55 cm 2 , 13.26 cm 2 , 16.23 cm 2 , 12.31 cm 2 (Figure 2,3). Discussion: The results support our hypothesis that high humidity level has a lower transpiration rate while hot wind has a higher transpiration rate compared to cold wind (Figure 1). Dry air lead to rapid closing of stomata while moist air allows the opening of stomata. The “humidity sensor” in the plant cell detects differences of water potential of air inside and outside of the plant’s leaf thus transpiration rate increase in drier environment (Lange 1971). In contrast, high humidity will provide a lower transpiration rate which is consistent with the result we found. Moreover, we detect a higher transpiration rate in environmental condition with wind blowing at it. According to Daubenmire, wind removes layers of humid air which accumulate on plant’s surface thus increases transpiration (1959). This is also consistent with the data found that plants given windy environment tend to have higher transpiration rate than standard control environment. In additional, high environmental temperature (38 to 40 degree Celsius) also increase stomatal opening hence increase water evaporation rate. On the other hand, lower temperature (0 to 8 degrees Celsius) prevents stomatal opening and lowers transpiration rate (Gates 1968). This is also evident in our data shown that hot wind has a higher transpiration rate than plant treated with cold wind. In conclusion, the transpiration rate response to environmental condition as an adaptation to maintain homeostasis.
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