How Do Living Things Get Energy?

1. How Do Living Things Get Energy? Ouch! Only female mosquitoes bite people and other animals. They need the blood to produce eggs. Lesson 2

2. Lesson 2 Vocabulary • Habitat—an environment that meets the needs of an organism. • Niche—the role of an organism in its habitat. • Food Chain—a series of organisms that depend on one another for food. • Prey—consumers that are eaten by predators. • Predator—a consumer that eats prey. • Food Web—a group of food chains that overlap. • Energy Pyramid—a diagram showing how much energy is passed from one organism to the next in a food chain.

3. Lesson 2 (page 174) Habitat • You probably wouldn’t see a heron in a desert or a penguin in a swamp. Animals must live in places that meet their needs. A habitat is an environment that meets the needs of a living thing. • Many habitats can overlap. For example, the three living things pictured on this page all live in a desert habitat. The desert meets all their needs.

4. Lesson 2 (page 175) Niche • Each living thing in a habitat has a role, or niche. The term niche describes how a living thing interacts with its habitat. • For example, a crab’s pointed claws and sharp eyes help it catch its food. • Part of the sidewinder’s (snake) niche is to eat small animals in its habitat. If all these snakes died, the desert would have too many mice, birds, and lizards.

5. Lesson 2 (page 176) • Living things depend on one another to live. A food chain is the movement of food energy in a sequence of living things. Every food chain starts with producers. • Consumers that are eaten are called prey. Prey are what is hunted. • A consumer that eats prey is a predator. Predators are the hunters. • Wolves are predators of antelope. They keep the population of antelope from increasing too much, so the antelope don’t eat all of the producers.

7. Lesson 2 (page 178) • A food chain shows how an animal gets energy from one food source. But food chains can overlap. One kind of producer may be food for different kinds of consumers. • Several food chains that overlap form a food web. There are food webs in water habitats, too. For example, herons eat snails, fish, and other birds. On the next page, you can see an ocean food web. It shows that energy moves from plankton, small producers in the ocean, to small fish.

9. Lesson 2 (page 180) Energy Pyramid • An energy pyramid shows how much energy is passed from one living thing to another along a food chain. Producers form the base of the pyramid. They use about 90 percent of the energy they get from the sun to grow. They store the other 10 percent in their stems, leaves, and other parts. • Next, consumers eat the producers. They get only the 10 percent of energy that the plants stored. These consumers use about 90 percent of the energy they get from the producers to grow and then store the other 10 percent in their bodies. That 10 percent is passed on to the consumers that eat them.

10. Lesson 2 Review! Put the living things in order to create a food chain.