Animal Classification and Characteristics

What is the primary characteristic scientists use to classify animals into two main groups?

• Their habitat

• Their size

• The presence or absence of a backbone

• Their diet

What term is used to describe animals that possess a backbone?

• Invertebrates

• Amphibians

• Vertebrates

• Mammals

Which of the following animals is an example of an invertebrate?

• Leopard

• Frog

• Jellyfish

• Puffin

What is the hard outer covering found on some invertebrates, such as crabs and insects, called?

• Endoskeleton

• Shell

• Exoskeleton

• Skin