Characteristics of Invertebrate Animals

What is a key characteristic that distinguishes invertebrate animals from vertebrate animals?

• They are all aquatic.

• They have an internal skeleton made of bones.

• They do not have bones.

• They are all terrestrial.

Which of the following describes sponges?

• They have gelatinous bodies and tentacles.

• They are soft and long, moving by dragging their bodies.

• They are aquatic, sac-shaped, and have bodies full of pores.

• They have calcareous plates forming a shell.

What is a common characteristic of mollusks?

• They are exclusively aquatic and covered in spines.

• They have soft bodies without legs and can be aquatic or terrestrial.

• They are the most abundant animals on Earth.

• They produce limestone residue to form beautiful shapes.

How are arthropods commonly classified?

• By the color of their external skeleton.

• By the number of legs they have.

• By their habitat (aquatic or terrestrial).

• By their ability to fly.