Animal Structure and Function

Chapter Introduction

Lesson 1: Support, Control, and Movement

Lesson 2: Circulation and Gas Exchange

Lesson 3: Digestion and Excretion

Chapter Wrap-Up

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CHAPTER INTRODUCTION

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Why do animals have different structures that perform similar functions?

Animal Structure and Function

CHAPTER INTRODUCTION

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Feathers for Hearing?

Look at the photo at the beginning of the chapter. The feathers around the great gray owl’s eyes enable it to hear better. The feathers form discs around the eyes that funnel sounds toward the owl’s ears.

• What other functions do you think feathers have for an owl?
• What other structures might enable the owl to survive?
• Why do animals have different structures that perform similar functions?

Animal Structure and Function

CHAPTER INTRODUCTION

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Animal Structure and Function

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Begin the lesson presentations for this chapter�before returning to the Chapter Wrap-Up.

Why do animals have different structures that perform similar functions?

Animals have different structures that perform similar functions to enable them to survive in different environments.

Animal Structure and Function

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CHAPTER WRAP-UP

Lesson 1: Support, Control, and Movement

• Support structures give internal organs protection. Endoskeletons are made of bone or cartilage. Exoskeletons are made of bone or cartilage. Exoskeletons form shells made of minerals.
• Nerve nets detect changes in the environment over a large area without a brain. Nerve cords sense the environment, send the information to the brain for processing, and transmit the response to neurons.
• Animals have different structures that enable them to move through their habitats.

Animal Structure and Function

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CHAPTER WRAP-UP

Lesson 2: Circulation and Gas Exchange

• Gas exchange occurs through gills in aquatic animals and through lungs or spiracles in terrestrial animals.
• In open circulatory systems, blood surrounds all organs in the body. Closed circulatory systems use blood vessels to transport substances throughout the body.

Animal Structure and Function

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CHAPTER WRAP-UP

Lesson 3: Digestion and Excretion

• An animal’s feeding structures depend on its diet. Animals that eat meat have sharp teeth that cut and tear, and animals that eat plants have wide, flat teeth for grinding.
• Aquatic animals use kidneys to excrete large amounts of water and ammonia. Terrestrial animals use kidneys to excrete smaller amounts of water and either urea or uric acid. Aquatic animals excrete carbon dioxide through gills, and terrestrial animals excrete carbon dioxide through the lungs or spiracles.

Animal Structure and Function

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CHAPTER WRAP-UP