Grade 8 Science : Main Biological Processes in Plants - Part 4

Guttation occurs when water is released/ exuded in the form of liquid by plants from structures called hydathodes that are present in leaves. We can observe water droplets on the tips and margins of certain plants like habarala, grass, and etc. at night. It should be noted that humidity or the amount of water vapor in the atmosphere is quite high at night where transpiration hardly takes place. This eventually leads to Guttation. It takes pace through the leaf margins of some plants like potato, and in the case of plants like habarala and grass, it happens through the leaf tips.  These water drops get evaporated during the day while the salts remain on the leaves. 

 

Both guttation and transpiration are biological processes that are vital for the systematic transportation of water and nutrients in plants. Both of these processes involve in losing water from the plants and they mainly take place through the leaf. In both instances, water is released through some special pores. Amidst the above similarities that can be observed among these biological processes, there are some noteworthy differences showcased by the same. 

 

 

Transpiration in plants take place through the stomata while guttation occurs through special pores called hydathodes in the leaves. Although water is lost by the plant in both the processes, the form in which it is lost differs. In transpiration, water is released as water vapor, where as it leaves plants in the form of liquid through guttation. Only water is lost through transpiration and it is pure. In contrast, both water and salts are lost when guttation takes place and it contains impurities. We discussed that guttation happens mostly during the night. However, transpiration occurs during day and night. When we consider the effect of atmospheric humidity on these two processes, the rate of transpiration reduces when humidity (amount of water vapor in the atmosphere) increases. On the other hand, when humidity is high, guttation too increases, which is why it mostly occurs at night. We learnt that humidity is high during the night time. If transpiration happens excessively, the plants may wilt/wither, whereas guttation will never result in wilting. 

 

 

 

 

 

 

 

by Mekhala Egodawele

Photo source : Internet