2. Another way scientist sort large groups of organisms is to classify them into groups with and without backbones.
A _______is a row of connected bones down the middle of the back. These bones are called _______.
________are animals that have backbones.
_________are animals without backbones.

3. Fish Vertebrates: Live in water Breathe with gills
Have scales and fins to help swim.
Reproduce by laying eggs.
Examples: tuna, perch, trout and carp.

4. 2. Amphibians Spend part of their lives in water and part on land.
Young have gills and breathe underwater.
Then they change form and develop lungs.
Adults breathe air and can live on land.
Smooth, moist skin
Most lay eggs in water
Examples: frogs, toads, newts and salamanders

5. 3. Reptiles Have lungs and scales Reproduce by laying eggs
Feet have claws
Cold-blooded
Examples: snakes, lizards, turtles, tortoises, alligators and crocodiles.

6. Cold-blooded - ectothermic
Most fish, amphibians and reptiles have body temperatures that change with their surroundings. When the water or air gets cooler, their bodies cool off too. Reptiles lie in sunlight to warm their bodies. They use shade to cool off.

7. 4. Birds Have feathers Beak, two feet and two wings
Most can fly, some can’t
Feed their young until they can find food on their own.
Keep a constant body temperature.
Warm-blooded - endothermic

8. 5. Mammals Have hair or fur Breathe through lungs
Grow inside mother’s body, fed milk from mother’s body
Keep a constant body temperature
Examples: whales, bears, cats, dogs, and humans

9. Invertebrates
95% of all animals are invertebrates- they do not have a backbone.
Examples: Spiders, lobsters, sponges, sea stars, and snails.
Some have a hard covering or shell
Spiders, insects, crabs, snails, clams
Other invertebrates, such as squid, jellyfish and earthworms, do not have a hard covering.

10. Vocabulary
Classify- to sort things into groups according to their characteristics.
Organism- a living thing
Producer- a living thing that makes its own food.
Consumer- a living thing that eats other living things to get energy.
Decomposer- a living thing that breaks down the remains of dead organisms to feed on them.
Backbone- a row of connected bones down the middle of the back.
Vertebrate- an animal that has a backbone.

11. Invertebrate- an animal that does not have a backbone.
Fish-a vertebrate that lives in water and breathes with gill. Most have scales and fins.
Reproduce- to make more of one’s own kind.
Amphibian- a vertebrate that lives part of its life in water and part on land.
Reptile- a vertebrate that breathes air and has scales or plates on its skin.
Bird-a vertebrate that breathes air, has wings and feathers, and lays eggs.
Mammal- a vertebrate that has hair or fur and feeds its young with milk from the mother’s body.