Wording of this Handout:
A tree is a common sight, but imagine if there was only one tree in the world, and people only got to see it once a year. Do you think it would be appreciated more if it was as rare as that?
Trees are made of tiny things called cells. If you hold a leaf up to the sun you should be able to see some of the cells.
Cells work together, like people in a family. There are special cells for carrying water, and cells for making roots, or buds, or tubes, or flowers, or for catching the sun.