Life Cycles — Answer Key
Part A: Sort the Words
Sort each word or number into the correct category box.
1. Sort each stage into the correct life cycle.
Frog Life Cycle
tadpolefrogletadult frog Chicken Life Cycle
chickhenegg with shell Tadpoles, froglets, and adult frogs are the growing stages of a frog. Chicks, hens, and hard-shelled eggs are stages of a chicken's life cycle.
Part B: Fill in the Blank
Write the missing word or number on each line.
1. A tadpole loses its tail as it grows into a frog.
Tadpoles swim with a tail, but adult frogs hop and do not need one. The tail slowly shrinks and disappears as the frog grows.
2. A chick grows feathers as it becomes an adult chicken.
A chick's soft down is replaced by bigger, stronger feathers as it grows up into an adult chicken. These feathers help keep the grown bird warm and dry.
3. Frog eggs are laid in clumps called spawn.
Frog eggs stick together in jelly-like clumps called spawn. Floating together helps keep the tiny eggs safe in ponds and streams.
4. A mother hen keeps her eggs warm for about 21 days.
A chick takes about three weeks to finish growing inside its egg, and 3 weeks x 7 days = 21 days. That is why hens sit on their eggs for about 21 days before they hatch.
5. Both frogs and chickens begin life inside an egg.
Many animals start out as eggs, and both frogs and chickens are in that group. Frogs lay eggs in water while chickens lay eggs with hard shells on land.
Part C: True or False?
Read each statement. Circle True or False.
1. A tadpole breathes with lungs right away.
True False
Young tadpoles live underwater and breathe with gills, like fish. Lungs grow later so the frog can breathe air once it lives on land.
2. A chick is covered in soft, fluffy down feathers.
True False
Newly hatched chicks are covered in fluffy down, which traps warm air close to their bodies. Stronger adult feathers grow in later as the chick gets older.
3. Frogs lay their eggs on dry land.
True False
Frogs lay their eggs in water, usually in ponds or quiet streams. The water keeps the eggs wet and lets tadpoles swim after they hatch.
4. A chicken life cycle starts with an egg.
True False
Every chicken begins as an egg laid by a hen. The chick grows inside the shell until it is ready to hatch.