Ch. 1 Lesson 4How are animals

classified?

vertebrate•animal with a backbone

5 classes

of vertebrates

mammals reptiles birds amphibians fish

Vertebrate Characteristics

Fish Scales, live in water, cold-blooded, lay eggs, gills

Amphibians Smooth skin, live in water and land, cold-blooded, lay eggs

Reptiles Scales, lay eggs, cold-blooded, lungs

Mammals Hair or fur, warm-blooded, live births, lungs

Birds Feathers, warm-blooded, lay eggs, lungs

invertebrates

mollusks worms arthropods

no backbone

cnidarians

arthropod

• largest group of invertebrates

• jointed legs

• divided into sections

• covered by hard exoskeleton

The Life Cycle of the Brown Garden Snail

1. lays its eggs

2. eggs hatch in 2-4 weeks

3. newly hatched snails must find food

4. adults reproduce

vertebrate

• animal with a backbone

5 classes

of vertebrates

mammals reptiles birds amphibians fish

invertebrate• animal without a backbone

arthropod• largest group of invertebrates

• jointed legs

• divided into sections

• covered by hard exoskeleton

invertebrates

•Which are there more of: vertebrates or invertebrates?

• Use a large space in a cafeteria, gymnasium, or playground to model the length of a giant squid by marking off a distance of 15 m. Use two basketballs to demonstrate the size of thesquid's eyes. Then, mark off a distance of 6 m so students can compare the length of a Burmese python with the length of the giant squid. Have students use a measuring tape tofind the lengths in feet and inches.

Activity-Compare Animal Sizes