Question

(B) Trees help to support man's life by supplying the atmo-
sphere with oxygen, which is essential to life. The oxygen in
the air is constantly being used up and turned into carbon diox-
ide when animals breathe and things burn. Carbon dioxide is
the food that plants eat. The green leaves of trees in fact, at all
green plants) absorb this carbon dioxide and with the help of
sunlight break it down into cabon and oxygen. The carbon is
used to make starch, and the oxygen is released into the air, so
replacing the oxygen used up by animals. But for this animals
would soon die for lack of oxygen.
Starch and other carbon compounds made in the green leaves
of trees and of other green plants too) serve as food for ani-
mals. The tiny green cells of plants are wonderful laboratories
which produce all the starch in the world. But for this service
done by plants animals would sooner or later die for lack of
food.
1. When is oxygen turned into carbon dioxide?
2. How is carbon dioxide used by trees?
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Answer 1

Explanation:

1. Day or in present of sunlight.

2.Tree convert the carbon dioxide to oxygen Which is very useful for all animals and trees.

Answer 2

Answer:

1. Oxygen is turned into carbon dioxide when animals use it for respiration.

2. The green leaves of trees absorb carbon dioxide with the help of sunlight and break it into carbon dioxide and oxygen. The carbon dioxide is used to make starch and oxygen is released into the air