Interactions and Dependencies in Ecosystems

1. Chapter Introduction Lesson 1 Ecosystems and Biomes Lesson 2 Populations and Communities Lesson 3Energy and Matter Chapter Wrap-Up Chapter Menu

2. How do living things interact with and depend on the other parts of an ecosystem? Chapter Introduction

3. What do you think? Before you begin, decide if you agree or disagree with each of these statements. As you view this presentation, see if you change your mind about any of the statements. Chapter Introduction

4. 1. An ecosystem contains both living and nonliving things. 2. All changes in an ecosystem occur over a long period of time. 3. Changes that occur in an ecosystem can cause populations to become larger or smaller. Do you agree or disagree? Chapter Introduction

5. 4. Some organisms have relationships with other types of organisms that help them to survive. 5. Most of the energy used by organisms on Earth comes from the Sun. 6. Both nature and humans affect the environment. Do you agree or disagree? Chapter Introduction

6. Ecosystems and Biomes • What are ecosystems? • What are biomes? • What happens when environments change? Lesson 1 Reading Guide - KC

7. Ecosystems and Biomes • ecosystem • abiotic factor • biotic factor • population • community • biome • succession Lesson 1 Reading Guide - Vocab

8. What are ecosystems? • Ecology is the study of how organisms interact with each other and with their environments. • Every organism on Earth lives in an ecosystem—the living and nonliving things in one place. • Different organisms depend on different parts of an ecosystem to survive. Lesson 1-1

9. Abiotic Factors • Abiotic factors are the nonliving parts of an ecosystem. • Important abiotic factors include water, light, temperature, atmosphere, and soil. • The types and amounts of abiotic factors in an ecosystem help to determine which organisms can live there. Lesson 1-2

10. Abiotic Factors(cont.) • All organisms need water to live, but some need more water than others. • The amount of light available and the temperature of an ecosystem can also determine which organisms can live there. • Different ecosystems contain different amounts and types of nutrients, minerals, and rocks in the soil. Lesson 1-2

11. Biotic Factors • Biotic factors are all of the living or once-living things in an ecosystem. • A population is made up of all the members of one species that live in an area. • Organisms in a population interact and compete for food, shelter, and mates. • A community is all the populations that live together in the same place. Lesson 1-3

12. Biotic Factors(cont.) • A biome is a large region on Earth with a specific climate, physical features, plants, and other organisms. • Biomes contain ecosystems, populations, and communities, as well as specific biotic and abiotic factors. • All biomes are part of the biosphere—the part of Earth that supports life—and can be described as either terrestrial or aquatic. Lesson 1-3

13. Biotic Factors(cont.) • Biomes, like communities, can affect each other. Lesson 1-3

14. What happens when environments change? • Changes in the environment are caused by both natural processes and human actions. • Changes in an environment can occur slowly or rapidly and can have positive or negative effects. Lesson 1-4

15. What happens when environments change?(cont.) • A volcanic eruption can cause sudden change in an ecosystem. • Succession is the gradual change from one community to another community in an area. Lesson 1-4

16. Biotic factors are the living parts of an ecosystem. • Earth’s biosphere contains many different biomes. • Changes in a community can be very slow or very rapid. Image by Reto Stockli, NASA/Goddard Space Flight Center. Enhancements by Robert Simmon Lesson 1 - VS

17. Which of these refers to the nonliving parts of an ecosystem? A. abiotic factors B. biotic factors C. biomes D. populations Lesson 1 – LR1

18. Which of these refers to all the populations that live together in the same place? A. ecosystem B. biosphere C. community D. biome Lesson 1 – LR2

19. The gradual change from one community to another community in an area is called what? A. succession B. population C. interaction D. community development Lesson 1 – LR3

20. 1. An ecosystem contains both living and nonliving things. 2. All changes in an ecosystem occur over a long period of time. Do you agree or disagree? Lesson 1 - Now

21. Populations and Communities • How do individuals and groups of organisms interact? • What are some examples of symbiotic relationships? Lesson 2 Reading Guide - KC

22. Populations and Communities • limiting factor • biotic potential • carrying capacity • habitat • niche • symbiotic relationship Lesson 2 Reading Guide - Vocab

23. Populations • The area in which a population lives can be very large, such as the population of all the fish in the ocean, or very small, like fish in a lake. • If either biotic or abiotic factors that affect an organism change, that organism’s population can also change. Lesson 2-1

24. Populations(cont.) • Sometimes the size of a population changes because the ecosystem changes. • Population density describes the number of organisms in the population relative to the amount of space available. • If a population is very dense, organisms might have a hard time finding enough resources to survive. Lesson 2-1

25. The size of a population can change in different ways. Lesson 2-1

26. Limiting factors are factors that can limit the growth of a population. Lesson 2-1

27. Populations(cont.) • Biotic potential is the potential growth of a population if it could grow in perfect conditions with no limiting factors. • Carrying capacity is the largest number of individuals that can survive in an area over a long time. • The limiting factors of an area determine the area’s carrying capacity. Lesson 2-1

28. Populations(cont.) • Overpopulation is when a population’s size grows beyond the ability of the area to support it. • This often results in overcrowding, a lack of resources, and an unhealthy environment. Lesson 2-1

29. Communities All the populations in the same area interact as a community. Lesson 2-2

30. Communities (cont.) Some populations might compete with each other for resources and space. How do the different populations in a lake interact with each other? Lesson 2-2

31. Symbiotic Relationships • Each population has different ways to stay alive and reproduce. • All of the populations in a community share a habitat, the physical place where a population or organism lives. • A niche is the unique ways an organism survives, obtains food and shelter, and avoids danger in its habitat. Lesson 2-3

32. Symbiotic Relationships(cont.) • A symbiotic relationship is one in which two different species live together and interact closely over a long period of time. • These relationships can be beneficial to both organisms, beneficial to one and harmful to the other, or beneficial to one and neutral to the other. Lesson 2-3

33. Types of Symbiotic Relationships • Mutualism—two species in a community benefit from the relationship. • Parasitism—one species (the parasite) benefits while another (the host) is harmed. • Commensalism—one species benefits and the other is neither helped nor harmed. Lesson 2-3

34. The factors that limit the size a population of organisms can reach are called limiting factors. • A habitat is the physical environment where a population of organisms lives. • A symbiotic relationship exists when two different species of organisms live together in a close relationship over a long period of time. Lesson 2 - VS

35. If a population’s rate of birth is as high as it can be while its death rate is as low as it can be, that population has reached which of these? A. limiting factor B. biotic potential C. population density D. carrying capacity Lesson 2 – LR1

36. Which of these determines an area’s carrying capacity? A. biotic potential B. population C. limiting factors D. habitat Lesson 2 – LR2

37. All of the populations in a community share which of these? A. carrying capacity B. habitat C. biotic potential D. limiting factor Lesson 2 – LR3

38. Do you agree or disagree? 3. Changes that occur in an ecosystem can cause populations to become larger or smaller. 4. Some organisms form relationships with other types of organisms that help them survive. Lesson 2 - Now

39. Energy and Matter • How does energy move in ecosystems? • How is the movement of energy in an ecosystem modeled? • How does matter move in ecosystems? Lesson 3 Reading Guide - KC

40. Energy and Matter • producer • consumer • food chain • food web • energy pyramid Lesson 3 Reading Guide - Vocab

41. Energy Flow • Organisms get energy from food that they make using light or chemical energy or by eating other organisms. • When one organism eats another, the energy in the organism that is eaten is transferred to the organism that eats it. Lesson 3-1

42. Energy Flow(cont.) • Energy travels through organisms, populations, communities, and ecosystems in a flow. • When energy moves in a flow it does not return to its source, as it does in cycles. Lesson 3-1

43. Organisms and Energy • Scientists classify organisms by the way they get the energy they need to survive. • Some organisms, such as plants, are able to capture the Sun’s energy directly and convert it into energy-rich sugars that they use for food. Lesson 3-2

44. Light energy is changed to food energy by a process called photosynthesis. Lesson 3-2

45. Organisms and Energy(cont.) • A few organisms are able to capture energy from chemicals in the environment and make food by a process called chemosynthesis. • Other organisms cannot capture energy from sunlight or chemicals and must obtain their energy by eating food. • Organisms that cannot make their own food using the Sun must depend on organisms that can. Lesson 3-2

46. Organisms and Energy(cont.) Producers change the energy available in their environment into food energy that they use to live and reproduce. producer from Latin producere, means “to lead” Lesson 3-2

47. Organisms and Energy(cont.) • Consumers use the energy and nutrients stored in other organisms for living and reproducing. • Consumers are classified as herbivores, omnivores, carnivores, or detritivores, based on their diet. • Herbivores are animals that eat only producers, such as plants. Lesson 3-2

48. Organisms and Energy(cont.) • Omnivores, such as human beings, are animals that eat both producers and other consumers. • Carnivores, such as lions, eat only other consumers. • Detritivores, including some insects, fungi, worms, bacteria, and protists, eat dead plant or animal material. Lesson 3-2

49. Modeling Energy Flow A food chain models how food energy moves from the environment to several organisms. Lesson 3-3

50. Modeling Energy Flow(cont.) • Each stage of a food chain has less available food energy than the last one, because some food energy is converted to thermal energy and moves to the environment. • A food web is a model that shows several connected food chains. Lesson 3-3