Unit 9 Lesson 3 How Do Animals Reproduce? Copyright © Houghton Mifflin Harcourt Publishing Company 1

Unit 9 Lesson 3 How Do Animals Reproduce? Florida Benchmark SC.4.L.16.4 Compare and contrast the major stages in the life cycles of Florida plants and animals, such as those that undergo incomplete and complete metamorphosis, and flowering and nonflowering seed-bearing plants. Copyright © Houghton Mifflin Harcourt Publishing Company 2

Life in Full Circle Most animals reproduce sexually. Unit 9 Lesson 3 How Do Animals Reproduce? Life in Full Circle Most animals reproduce sexually. During sexual reproduction, sperm from a male joins an egg from a female. Copyright © Houghton Mifflin Harcourt Publishing Company 3

Unit 9 Lesson 3 How Do Animals Reproduce? Life in Full Circle In some animals, such as birds, fertilized eggs form inside the female’s body. In some animals, such as many kinds of fish, fertilized eggs form outside the female’s body. Copyright © Houghton Mifflin Harcourt Publishing Company 4

Life in Full Circle A fertilized egg grows into a new animal. Unit 9 Lesson 3 How Do Animals Reproduce? Life in Full Circle A fertilized egg grows into a new animal. After the young are born, they grow and change. Over time, newborns grow into youth and youth grow into adults. Adults have their own young, and the life cycle continues. Copyright © Houghton Mifflin Harcourt Publishing Company 5

Unit 9 Lesson 3 How Do Animals Reproduce? Bringing Up Baby Some animals, such as turtles, receive no care from their parents. Other animals, such as penguins, take care of their young until they can take care of themselves. Copyright © Houghton Mifflin Harcourt Publishing Company 6

Unit 9 Lesson 3 How Do Animals Reproduce? Bringing Up Baby Animals such as deer, bears, rabbits, cats, and kangaroos take care of their young by feeding them milk. These animals care for their young for months or years until the young can live on their own. Copyright © Houghton Mifflin Harcourt Publishing Company 7

Unit 9 Lesson 3 How Do Animals Reproduce? Growing Up Just like other animals, humans go through stages of development. It takes many years for a human baby to grow into an adult. Copyright © Houghton Mifflin Harcourt Publishing Company 8

Growing Up Human babies grow inside the mother. Unit 9 Lesson 3 How Do Animals Reproduce? Growing Up Human babies grow inside the mother. After nine months, the baby is born. The baby matures into a toddler, then a child, then a teenager, and then an adult. Copyright © Houghton Mifflin Harcourt Publishing Company 9

Unit 9 Lesson 3 How Do Animals Reproduce? My, How You’ve Changed! In complete metamorphosis, an animal goes through four different stages in its life cycle. The egg hatches into a larva. The larva develops into a pupa. The pupa develops into an adult. Copyright © Houghton Mifflin Harcourt Publishing Company 10

Unit 9 Lesson 3 How Do Animals Reproduce? My, How You’ve Changed! What are the stages in a butterfly’s life cycle? Copyright © Houghton Mifflin Harcourt Publishing Company 11

Unit 9 Lesson 3 How Do Animals Reproduce? My, How You’ve Changed! In incomplete metamorphosis, an animal goes through three different stages in its life cycle. First, the animal hatches from an egg as a nymph. Nymphs look like tiny adults. The nymph grows into an adult. Copyright © Houghton Mifflin Harcourt Publishing Company 12

Unit 9 Lesson 3 How Do Animals Reproduce? My, How You’ve Changed! What are the stages in the life cycle of a grasshopper? Copyright © Houghton Mifflin Harcourt Publishing Company 13

Unit 9 Lesson 3 How Do Animals Reproduce? Saving the Sea Turtles Some kinds of animals, such as sea turtles, are endangered. There are not many of them left. Scientists study the animal’s life cycle and try to increase the number of them in nature. Copyright © Houghton Mifflin Harcourt Publishing Company 14