1. Organisms

2. An organism is a living thing.
How are trees, dogs, mushrooms, and worms the same? Each is an organism.
An organism is a living thing.

3. Animals Alive What do organisms need to stay alive?
All organisms need food, water, shelter, and air.
An organism is a living thing.
You are an organism. Animals and plants are also organisms.
Organisms find what they need in their environment.
Animals Alive

4. Organisms’ Needs Organisms’ Specific Needs
Each kind of organism has its own specific needs, such as the type of food and shelter it needs, and the amount of water, light, and space it needs.
A dog needs dog food. A worm needs worm food.
Organisms grow, change, and die over time.
Are cows organisms?
Organisms’ Needs

5. You Are an Organism What do you need to stay alive? You need food.
You need water.
You need air.
You Are an Organism

6. Plants Alive Plants make their own food.
They need a specific amount of light.
They need a specific amount of water.
They need air.
They need specific nutrients in soil.
Plants use these things to make food.
Plants Alive

7. Alive in a Tree Cardinals need plants. Cardinals eat seeds and fruit.
Seeds and fruit are parts of plants.
Alive in a Tree

8. Alive in a Tree A squirrel has its nest in a tree.
It eats seeds and nuts.
Squirrels store food.
They may not eat all the food they store.
Some of the nuts may grow to be new plants.
Alive in a Tree

9. Alive in a Flower Garden
Bees and flowers are partners.
Bees go from flower to flower.
They gather nectar. They spread pollen.
Bees need nectar to make honey.
Flowers need pollen to make seeds.
Alive in a Flower Garden

10. Alive in the Dirt This earthworm eats dirt.
It gets the water it needs from dirt.
It gets its food from dirt.
It leaves behind nutrients that plants need.
Earthworms make tunnels as they eat.
The tunnels leave room for plant roots to grow.
Alive in the Dirt

11. Animals on the Ground Pillbugs
A pill bug is not an insect. A pill bug is an isopod. Pill bugs are related to crabs, lobsters, and shrimp. Pill bugs are not usually seen out and about. They are usually nocturnal. Pill bugs need moisture at all times, because they breathe through gills. They are most often found under wood, bark, or leaves. Pill bugs have strong jaws so that they can bite into stems and roots. They help plants because they return nutrients to the soil, but if there are too many pill bugs they can damage plants. Pill bugs feed on live and dead plant material.
Animals on the Ground

12. Animals on the Ground Pillbugs
A pill bug’s predators are birds, lizards, and spiders. A pill bug’s defense is to roll into a ball to protect its softer underside. A pill bug can also move quickly.
Animals on the Ground

13. Animals on the Ground Pillbugs
A pill bug has a small head with 2 long antennae. It has 14 legs, but only 12 legs when it is very young. The pill bug’s eyes are on the side of its head. The pill bug had no bones. It has a hard exoskeleton made of chitin. Chitin is a hard material similar to your fingernail. Because the exoskeleton cannot grow, a pill bug must molt in order to grow. If a pill bug is light gray or brown, it is getting ready to molt or it just molted.  
Animals on the Ground

14. Animals on the Ground Pillbugs
A pill bug mom can carry up to 200 eggs in a pouch under the front end of her body. The eggs hatch in the pouch, where they stay for about three weeks. When they come out of the pouch, they are small and very pale and may be hard to see.
Animals on the Ground