Animal Groups — Answer Key
Part A: Multiple Choice
Circle the best answer for each question.
1. Which animal is a reptile?
A) dog
B) turtle
C) robin
D) goldfish
A turtle has dry, scaly skin and lays eggs on land, the features that mark a reptile. A dog is a mammal, a robin is a bird, and a goldfish is a fish.
2. What do all mammals have?
A) scales
B) feathers
C) fur or hair
D) fins
Fur or hair covers every mammal and helps keep its body warm. Scales belong to fish and reptiles, feathers belong to birds, and fins are for swimming.
3. Which animal is an insect?
A) frog
B) shark
C) eagle
D) ant
An ant has six legs and three body parts, which are the marks of an insect. A frog is an amphibian, a shark is a fish, and an eagle is a bird.
4. How do fish breathe?
A) with lungs
B) with gills
C) with skin
D) with feathers
Fish take in water through their gills, and the gills pull oxygen out of the water. Lungs are used by mammals and birds, not by fish.
Part B: Fill in the Blank
Write the correct answer on each line.
1. Amphibians can live on land and in water.
Amphibians like frogs start life as tadpoles in water and move onto land as adults, so they need water for part of their life.
2. Birds have feathers to keep them warm.
Feathers trap warm air close to a bird's skin, which helps it stay warm even on cold days.
3. A cobra is a reptile.
Dry, scaly skin, eggs laid on land, and a cold-blooded body are the marks of a reptile, and a cobra has them all.
4. Mammals feed their babies milk.
Mammal mothers make milk in their bodies and feed it to their babies until the babies can eat other food on their own.
5. A grasshopper is an insect.
With six legs, three body parts, and antennae, a grasshopper has the features that put an animal in the insect group.