Grade 1
The Human Knowledge Project
Unit 14 — Food Chains and Ecosystems
Welcome back!
Have you ever wondered how living things depend on one another?
Plants, animals, and people are all connected.
Scientists call these connections an ecosystem.
Today we will discover how living things work together in nature.
What Is an Ecosystem?
An ecosystem is a place where living things and nonliving things interact.
An ecosystem includes:
- plants
- animals
- insects
- soil
- rocks
- water
- air
- sunlight
Every part plays an important role.
Plants Make Food
Plants are special.
Using sunlight, water, and air, they make their own food.
Because of this, plants are called producers.
Without plants, most other living things could not survive.
Animals Eat Plants and Other Animals
Animals cannot make their own food.
Some animals eat plants.
These are called plant eaters, or herbivores.
Some animals eat other animals.
These are called meat eaters, or carnivores.
Some animals eat both plants and animals.
These are called omnivores.
People are omnivores because we eat many different kinds of food.
A Simple Food Chain
A food chain shows how energy moves from one living thing to another.
Here is an example:
Grass
↓
Rabbit
↓
Fox
The rabbit eats the grass.
The fox eats the rabbit.
Every living thing depends on something else.
Many Food Chains
Nature has many food chains.
For example:
Leaves
↓
Caterpillar
↓
Bird
↓
Hawk
Every ecosystem contains many different connections.
Caring for Nature
Healthy ecosystems need clean:
- water
- air
- soil
People can help nature by:
- planting trees
- recycling
- picking up litter
- protecting wildlife
- saving water
Small actions can make a big difference.
Activity
Draw a simple food chain using three or four living things.
Example:
Grass
↓
Grasshopper
↓
Frog
↓
Snake
Can you create one using animals that live near your home?
Practice
Answer these questions.
What is an ecosystem?
Why are plants called producers?
What is a herbivore?
What is a carnivore?
How can people help protect nature?
Review
Today you learned:
- ecosystems connect living and nonliving things
- plants make their own food
- animals depend on plants and other animals
- food chains show how living things are connected
- people can help protect ecosystems
Nature is like a giant team, with every living thing playing an important part.
Looking Ahead
Next we will explore weather.
We will discover:
- sunshine
- clouds
- rain
- wind
- storms
- seasons
Weather changes every day and affects all living things.