1. How to Use This Presentation To View the presentation as a slideshow with effects select “View” on the menu bar and click on “Slide Show”, or simply press F5 on the top row of your keyboard. To advance to the next slide click the left mouse button once. From the Chapter screen you can click on any section to go directly to that section’s presentation. Blank or “missing” areas of a slide will remain hidden until the left mouse button is clicked. You may exit the slide show at any time by pressing the Esc key Copyright © by Holt, Rinehart and Winston. All rights reserved.

2. Interactions of Living Things Chapter 18 Section 1: Everything Is Connected Section 2: Living Things Need Energy Section 3: Types of Interactions Copyright © by Holt, Rinehart and Winston. All rights reserved. End of Slide

3. Everything Is Connected Section 1 Bellringer Think of all the things that make up a pond in the countryside. List all the parts of the pond’s ecosystem in your science journal. Then draw an illustration of a pond ecosystem. Are all the parts of the ecosystem living? Explain your answer. Copyright © by Holt, Rinehart and Winston. All rights reserved.

4. Everything Is Connected Section 1 Objectives Distinguish between the biotic and abiotic parts of the environment. Explain how populations and communities are related. Describe how the abiotic parts of the environment affect ecosystems. Copyright © by Holt, Rinehart and Winston. All rights reserved. End of Slide

5. Everything Is Connected Section 1 Studying the Web of Life The Two Parts of the Environment All of the organisms that live together and interact with one another make up the biotic part of the environment. The abiotic part of the environment consists of the nonliving factors. Organization in the Environment At first glance, the environment may seem disorganized. However, the environment can be arranged into different levels. Populations Each animal is a part of a population, or a group of individuals of the same species that live together. Copyright © by Holt, Rinehart and Winston. All rights reserved. End of Slide

6. Everything Is Connected Section 1 Copyright © by Holt, Rinehart and Winston. All rights reserved. Communities A community consists of all of the populations of species that live and interact in an area. Ecosystems An ecosystem is made up of a community of organisms and the abiotic environment of the community. The Biosphere The biosphere is the part of Earth where life exists. Studying the Web of Life continued End of Slide

7. Living Things Need Energy Section 2 Bellringer Indian pipe is a plant that is completely white—it has no chlorophyll or chloroplasts to give it a green color. Do you think this plant could be a producer? If not, where do you think it could get the energy it needs to survive? Write your answers in your science journal. Copyright © by Holt, Rinehart and Winston. All rights reserved.

8. Living Things Need Energy Section 2 Objectives Describe the functions of producers, consumers, and decomposers in an ecosystem. Distinguish between a food chain and a food web. Explain how energy flows through a food web. Describe how the removal of one species affects the entire food web. Copyright © by Holt, Rinehart and Winston. All rights reserved. End of Slide

9. Living Things Need Energy Section 2 The Energy Connections Producers Organisms that use sunlight directly to make food are called producers. Consumers Organisms that eat other organisms are called consumers. Decomposers Organisms that get energy by breaking down dead organisms are called decomposers. Copyright © by Holt, Rinehart and Winston. All rights reserved. End of Slide

10. Living Things Need Energy Section 2 The Energy Connections continued Food Chains and Food Webs A food chain is a diagram that shows how energy in food flows from one organism to another. A food web is a diagram that shows the feeding relationships between organisms in an ecosystem. Energy Pyramids An energy pyramid is a diagram that shows an ecosystem’s loss of energy. An example of an energy pyramid is shown on the next slide. Copyright © by Holt, Rinehart and Winston. All rights reserved. End of Slide

11. Energy Pyramid Section 2 Copyright © by Holt, Rinehart and Winston. All rights reserved.

12. Living Things Need Energy Section 2 Wolves and the Energy Pyramid Gray Wolves and the Food Web Gray wolves were brought back to Yellowstone National Park in 1995. The U.S. Fish and Wildlife Service thinks the return of the wolves will restore the natural energy flow in the area, bring populations back into balance, and help the park’s environment remain healthy. Balance in Ecosystems All organisms in a food web are important for the health and balance of all other organisms in the food web. Copyright © by Holt, Rinehart and Winston. All rights reserved. End of Slide

13. Types of Interactions Section 3 Bellringer Make a list of predators that are also prey. Then list some animals that are only predators or only prey. Why do you think some animals fit in only one of these roles while others can sometimes be predators and other times be prey? Record your answer in your science journal. Copyright © by Holt, Rinehart and Winston. All rights reserved.

14. Types of Interactions Section 3 Objectives Explain the relationship between carrying capacity and limiting factors. Describe the two types of competition. Distinguish between mutualism, commensalism, and parasitism. Give an example of coevolution. Copyright © by Holt, Rinehart and Winston. All rights reserved. End of Slide

15. Types of Interactions Section 3 Interactions with the Environment Copyright © by Holt, Rinehart and Winston. All rights reserved. Limiting Factors A resource that is so scarce that it limits the size of a population is called a limiting factor. Carrying Capacity The largest population that an environment can support is known as the carrying capacity. End of Slide

16. Types of Interactions Section 3 Interactions Between Organisms Copyright © by Holt, Rinehart and Winston. All rights reserved. Individuals and Populations Interact Populations contain individuals of a single species that interact with one another, such as a group of rabbits feeding in the same area. Communities contain interacting populations, such as a coral reef with many species of corals trying to find living space. Individuals and Populations Interact When two or more individuals or populations try to use the same resource, such as food, water, shelter, space, or sunlight, it is called competition. Competition End of Slide

17. Types of Interactions Section 3 Predators and Prey Copyright © by Holt, Rinehart and Winston. All rights reserved. Predator Adaptations To survive, predators must be able to catch their prey. Predators have a wide variety of methods and abilities for doing so. Prey Adaptations Prey have their own methods and abilities to keep from being eaten. Prey are able to run away, stay in groups, or camouflage themselves. Some prey are poisonous. Camouflage One way animals avoid being eaten is by being hard to see. Blending in with the background is called camouflage. End of Slide

18. Types of Interactions Section 3 Predators and Prey continued Copyright © by Holt, Rinehart and Winston. All rights reserved. Defensive Chemicals Some animals defend themselves with chemicals. The skunk and the bombardier beetle both spray predators with irritating chemicals. Bees, ants, and wasps inject a powerful acid into their attackers. Warning Coloration Animals that have a chemical defense need a way to warn predators that they should look elsewhere for a meal. Their chemical weapons are often advertised by warning colors. End of Slide

19. Types of Interactions Section 3 Symbiosis Copyright © by Holt, Rinehart and Winston. All rights reserved. Mutualism A symbiotic relationship in which both organisms benefit is called mutualism. Commensalism A symbiotic relationship in which one organism benefits and the other is unaffected is called commensalism. Parasitism A symbiotic association in which one organism benefits while the other is harmed is called parasitism. End of Slide

20. Types of Interactions Section 3 Coevolution Copyright © by Holt, Rinehart and Winston. All rights reserved. What Is Coevolution? When a long-term change takes place in two species because of their close interactions with one another, the change is called coevolution. Coevolution and Flowers Flowers have changed over millions of years to attract pollinators. Pollinators such as bees, bats, and hummingbirds can be attracted to a flower because of its color, odor, or nectar. End of Slide

21. Interactions of Living Things Chapter 18 Concept Map Copyright © by Holt, Rinehart and Winston. All rights reserved. Use the following terms to complete the concept map on the next slide: carnivores, environment, sunlight, communities, biosphere, herbivores, ecosystem, populations, consumers.

22. Concept Map Chapter 18 Copyright © by Holt, Rinehart and Winston. All rights reserved.

23. Concept Map Chapter 18 Copyright © by Holt, Rinehart and Winston. All rights reserved.