Experiment 10 — How Water Travels Up a Plant

Topic: Biology · Classes 4–5 · Parts of a plant and their functions

Aim: Get the coloured water to reach the leaves within a day.

Daily: This is how a tall neem tree lifts water from its roots to leaves many metres above the ground — with no pump at all. It is also why cut flowers droop when you forget to change their water.

Obs: The water level did not fall at all, and nothing rose up the stem.

Should: Remove the wax and use a fresh cut . Water enters through the open tubes at the cut end; sealing them blocks the only doorway.

Why it happens: Inside a stem are narrow tubes called xylem , running from the roots to every leaf. Water rises through them. If the tube openings are sealed or dried shut, nothing can enter.

Question: Which plant will draw up water fastest?

Exp: Evaporation from the leaves does the pulling, and warm moving air speeds it up.

Question: Water travels up a stem through tubes called…

Exp: Xylem tubes run from root to leaf.

Question: The pull that lifts water comes mainly from…

Exp: As water leaves the pores, it drags the column up behind it.

Question: Plants wilt on a hot dry day because…

Exp: Transpiration exceeds the water taken up.

Question: Why use dye in this experiment?

Exp: The dye is a tracer; it shows where water has travelled.