Question

Which one is correct for secretion of guttation-
A. Pure water
B. Water with salts
C. Water with excretory product
D. Water with organic minerals

Answer 1

Hint: The word guttation means losing water in the form of liquid droplets. Guttation is a process through which plants maintain the amount of water in them.

Step by step answer:Guttation is a phenomenon shown by some plants in which water is lost in the form of droplets via the margins and tips by the leaves. This process occurs mostly in small plants possessing vascular systems as the pressure required to do this process is very little for small plants. It is a mechanism opted by plants to eliminate excess water. This process occurs especially at night when transpiration is almost halted entirely. When the water content in soil is more, roots start to absorb water even though there is no need for water in plants. So the extra water is pushed out of the plant through guttation. Along with water some inorganic salts also excrete via this secretion. The process of guttation occurs through specialized pores called hydathodes. They should not be confused with stomata, as stomata can be opened and closed but hydathodes cannot. They are pores that are used just for guttation. Along with water organic substances like salts are also pushed out through hydathode. Hence the correct answer is option B, i.e., water with salts
Additional information: the secretion during guttation is commonly called ‘xylem sap’. Guttation is not dew, as dew is simply water droplets condensed on the leaves but guttation is the secretion which is given out by leaf margins and tips.

Note: The term guttation and transpiration are different from each other. Even though both are associated with loss of water, there are significant differences among them. Water is lost as water vapour during transpiration and in guttation, it is lost as liquid droplets. When the transpiration happens, stomata are open but when guttation occurs, stomata are closed as guttation occurs at night time. Transpiration occurs when the temperature is high, guttation occurs at relatively low temperature.