The loss of water in the form of liquid occurs through . . . . . . .

Which of the following is $NOT$ included in the stomatal apparatus?

Stomatal index $(I)$ is equal to:

Which of the following is ineffective on transpiration?

Under what conditions does the rate of transpiration increase?

Water moves up against gravity and even for a tree of $20 \,m$ height, the tip receives water within two hours. The most important physiological phenomenon which is responsible for the upward movement of water is $...........$