1. Unit 4 Lesson 1 What Are Ecosystems?
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2. Animals and Plants at Home
Unit 4 Lesson 1 What Are Ecosystems?
Animals and Plants at Home
Everything that surrounds a living thing is its environment.
This includes living and nonliving things.
Your desk, teacher, and books are all part of your classroom environment. So is the air.
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3. Animals and Plants at Home
Unit 4 Lesson 1 What Are Ecosystems?
Animals and Plants at Home
An ecosystem is all of the living and nonliving things in a place.
In an ecosystem, living things interact with each other and the nonliving parts of their environment.
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4. Animals and Plants at Home
Unit 4 Lesson 1 What Are Ecosystems?
Animals and Plants at Home
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5. Animals and Plants at Home
Unit 4 Lesson 1 What Are Ecosystems?
Animals and Plants at Home
Living things in the same ecosystem share resources.
Many of them also share a habitat.
A habitat is the space where a plant or an animal lives.
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6. Animals and Plants at Home
Unit 4 Lesson 1 What Are Ecosystems?
Animals and Plants at Home
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7. Animals and Plants at Home
Unit 4 Lesson 1 What Are Ecosystems?
Animals and Plants at Home
A bird’s habitat is a forest. A bird’s environment is everything around it.
Take a look at this forest. What kinds of things are in the bird’s environment?
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8. Communities of Populations
Unit 4 Lesson 1 What Are Ecosystems?
Communities of Populations
Wolves, bears, snakes, birds, and many other plants and animals live in Yellowstone National Park.
A population is all of one kind of organism living in the same area.
All the wolves in Yellowstone National Park make up the wolf population there.
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9. Communities of Populations
Unit 4 Lesson 1 What Are Ecosystems?
Communities of Populations
Animal and plant populations in an area may be part of the same community.
A community is all of the populations that live and interact in an area.
An ecosystem can have many different communities. For example, a bull snake is part of the Yellowstone National Park community along with wolves and bison.
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10. Communities of Populations
Unit 4 Lesson 1 What Are Ecosystems?
Communities of Populations
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11. Unit 4 Lesson 1 What Are Ecosystems?
Living on the Land
There are many different ecosystems on land. Forest ecosystems have lots of trees.
Ecosystems found on the high sides of mountains are cold most of the year.
Desert ecosystems have plants and animals with adaptations that help them survive in dry areas.
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12. Living on the Land Unit 4 Lesson 1 What Are Ecosystems? 12
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13. Unit 4 Lesson 1 What Are Ecosystems?
Under the Water
A lot of the planet is covered in water. This means there are a lot of ocean ecosystems.
Animals like sea turtles and whales live in ocean waters.
Fresh water ecosystems have much less salt than ocean waters. Frogs, ducks, and many kinds of fish live in rivers, lakes, ponds, and streams.
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14. Under the Water Unit 4 Lesson 1 What Are Ecosystems? 14
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15. Under the Water Unit 4 Lesson 1 What Are Ecosystems? 15
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16. Under the Water Unit 4 Lesson 1 What Are Ecosystems? 16
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