Animal Characteristics

Which of the following are found in vertebrates to support their bodies?

• Backbones only

• Backbones and endoskeletons

• Backbones and exoskeletons

• Endoskeletons and exoskeletons

Complete the table below to describe the fate of each of the three layers formed during the early development of an animal.

Answer explanation

______________ fertilization occurs when the sperm and egg combine outside the animal’s body and it______________ a water environment.

• External , does not require

• External, requires

• Internal, does not require

• Internal, requires

If the sperm of a male parrotfish is carried away from the female’s eggs by ocean currents, which structure cannot form to begin the life of a new parrotfish?

• Blastula

• Embryo

• Gastrula

• Zygote

Use the diagram below to complete the table that follows.

Which of the following are among the general characteristics of animals? I. All animals are multicellular II. Animal cells do not have cell walls III. Some animals are autotrophs and some are heterotrophs

• I and II only

• I and III only

• II and III only

• I, II and III

Which of the following are among the ways used by animals to digest their food? I. Digestion inside certain cells II. Digestion in organs or cavities inside their bodies III. Digestion outside their bodies

• I and II only

• I and III only

• II and III only

• I, II and III

What is the process called when an animal's sperm and egg combine outside the body in a water environment?

• External fertilization

• Internal fertilization

• External reproduction

• Internal reproduction

Which of the following is NOT a general characteristic of animals?

• All animals are multicellular

• Animal cells do not have cell walls

• Some animals are autotrophs and some are heterotrophs

• All animals are autotrophs

How do animals primarily digest their food?

• Through photosynthesis

• By absorbing nutrients through their skin

• By digestion inside certain cells or organs

• By excreting the food whole