All the animals on Earth need to breathe the oxygen in air to stay alive - and that includes humans. That's because bodies use oxygen to make energy for living and growing.
All plants need air, light and water to live and grow. So do people, and every other living thing on our planet.
Even thought they live in the sea, whales breathe oxygen from the air. Sperm whales can hold their breathe for up to 2 hours before coming up for air.
Question:
Why do we need light?
Answer:
Without the sun's light, there would be nothing to eat. Plants are the only living things that can make their own food, and they need sunlight to do this. Everything else on Earth feeds on plants, or on plant-eating animals. If there weren't any plants, we'd all starve to death.
Question:
Why do we need water?
Answer:
It's hard to imagine, but more than two-thirds of our body is made of water. And the same true for most other animals and plants. All of the living things on Earth need water to stay alive. Without it, they would die.
You can survive for many weeks without food. But without water, you'd last just three or four days.
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Question:
Why do we need air?
Answer:
All the animals on Earth need to breathe the oxygen in air to stay alive - and that includes humans. That's because bodies use oxygen to make energy for living and growing.
Question:
Why do we need light?
Answer:
Without the sun's light, there would be nothing to eat. Plants are the only living things that can make their own food, and they need sunlight to do this. Everything else on Earth feeds on plants, or on plant-eating animals. If there weren't any plants, we'd all starve to death.
Question:
Why do we need water?
Answer:
It's hard to imagine, but more than two-thirds of our body is made of water. And the same true for most other animals and plants. All of the living things on Earth need water to stay alive. Without it, they would die.