Trees are an important part of our world. They provide ____ for building and pulp for making ____. Trees also help to keep our ____ clean and our ecosystems healthy. We breathe in ____ and breathe out ____. The roots are the part of the tree that grows ____. Trees have a lot of ____, the size of the root system is usually as big as the part of the tree above the ground. The crown is made up of the ____ and branches at the top of a tree. The crown shades the roots, collects energy from the ____ (photosynthesis) and allows the tree to remove extra water to keep it ____ Leaves are the part of the ____ of a tree. They are the part of the tree that converts energy into ____ (sugar). Leaves are the food factories of a tree.

TREES

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