Table of Contents – pages iv-v Unit 1:What is Biology? Unit 2:Ecology Unit 3:The Life of a Cell Unit 4:Genetics Unit 5:Change Through Time Unit 6:Viruses, Bacteria, Protists, and Fungi Unit 7:Plants Unit 8:Invertebrates Unit 9:Vertebrates Unit 10:The Human Body
Table of Contents – pages iv-v Unit 1: What is Biology? Chapter 1:Biology: The Study of Life Unit 2: Ecology Chapter 2:Principles of Ecology Chapter 3:Communities and Biomes Chapter 4:Population Biology Chapter 5:Biological Diversity and Conservation Unit 3:The Life of a Cell Chapter 6:The Chemistry of Life Chapter 7:A View of the Cell Chapter 8:Cellular Transport and the Cell Cycle Chapter 9:Energy in a Cell
Unit 4: Genetics Chapter 10:Mendel and Meiosis Chapter 11:DNA and Genes Chapter 12:Patterns of Heredity and Human Genetics Chapter 13:Genetic Technology Unit 5: Change Through Time Chapter 14:The History of Life Chapter 15:The Theory of Evolution Chapter 16:Primate Evolution Chapter 17:Organizing Life’s Diversity Table of Contents – pages iv-v
Unit 6: Viruses, Bacteria, Protists, and Fungi Chapter 18:Viruses and Bacteria Chapter 19:Protists Chapter 20:Fungi Unit 7: Plants Chapter 21:What Is a Plant? Chapter 22:The Diversity of Plants Chapter 23:Plant Structure and Function Chapter 24:Reproduction in Plants Table of Contents – pages iv-v
Table of Contents – pages iv-v Unit 8: Invertebrates Chapter 25:What Is an Animal? Chapter 26:Sponges, Cnidarians, Flatworms, and Roundworms Chapter 27:Mollusks and Segmented Worms Chapter 28:Arthropods Chapter 29:Echinoderms and Invertebrate Chordates
Table of Contents – pages iv-v Unit 9: Vertebrates Chapter 30:Fishes and Amphibians Chapter 31:Reptiles and Birds Chapter 32:Mammals Chapter 33:Animal Behavior Unit 10: The Human Body Chapter 34:Protection, Support, and Locomotion Chapter 35:The Digestive and Endocrine Systems Chapter 36:The Nervous System Chapter 37:Respiration, Circulation, and Excretion Chapter 38:Reproduction and Development Chapter 39:Immunity from Disease
Unit Overview – pages 32-33 Ecology Principles of Ecology Communities and Biomes Population Biology Biological Diversity and Conservation
Chapter Contents – page vii Chapter 3Communities and Biomes 3.1:Communities 3.1:Section Check 3.2:Biomes 3.2:Section Check Chapter 3 Summary Chapter 3Assessment
Chapter Intro-page 64 What You’ll Learn You will identify factors that limit the existence of species to certain areas. You will describe how and why different communities form. You will compare and contrast biomes of Earth.
3.1 Section Objectives – page 65 Section Objectives: • Identify some common limiting factors. • Explain how limiting factors and ranges of tolerance affect distribution of organisms. • Sequence the stages of ecological succession. • Describe the conditions under which primary and secondary succession take place.
Section 3.1 Summary – pages 65-69 Life in a Community • Various combinations of abiotic and biotic factors interact in different places around the world.
Section 3.1 Summary – pages 65-69 Life in a Community • The result is that conditions in one part of the world are suitable for supporting certain forms of life, but not others.
Section 3.1 Summary – pages 65-69 Limiting factors • Factors that affect an organism’s ability to survive in its environment, such as the availability of water and food, predators, and temperature, are called limiting factors.
Section 3.1 Summary – pages 65-69 Common Limiting Factors Limiting factors Sunlight • A limiting factor is any biotic or abiotic factor that restricts the existence, numbers, reproduction, or distribution of organisms. Climate Atmospheric gases Temperature Water Nutrients/Food Fire Soil chemistry Space Other organisms
Section 3.1 Summary – pages 65-69 Limiting factors • Factors that limit one population in a community may also have an indirect effect on another population.
Section 3.1 Summary – pages 65-69 Ranges of tolerance • The ability of an organism to withstand fluctuations in biotic and abiotic environmental factors is known as tolerance. Limits of Tolerance Organisms absent Organisms absent Organisms infrequent Organisms infrequent Greatest number of organisms Zone of Physiological stress Zone of Physiological stress Zone of intolerance Zone of intolerance Population Optimum range Range of tolerance Lower limit Upper limit
Section 3.1 Summary – pages 65-69 Succession: Changes over Time • Ecologists refer to the orderly, natural changes and species replacements that take place in the communities of an ecosystem as succession. • Succession occurs in stages. At each stage, different species of plants and animals may be present.
Section 3.1 Summary – pages 65-69 Succession: Changes over Time • As succession progresses, new organisms move in. • Others may die out or move out. • There are two types of succession—primary and secondary.
Section 3.1 Summary – pages 65-69 Primary succession • The colonization of barren land by communities of organisms is called primary succession. • Primary succession takes place on land where there are no living organisms.
Section 3.1 Summary – pages 65-69 Primary succession • The first species to take hold in an area like this are called pioneer species. • An example of pioneer species is a lichen, which is a combination of small organisms.
Section 3.1 Summary – pages 65-69 Primary succession • Decaying lichens, along with bits of sediment in cracks and crevices of rock, make up the first stage of soil development. • New soil makes it possible for small weedy plants, small ferns, fungi, and insects to become established.
Section 3.1 Summary – pages 65-69 Primary succession • As these organisms die, more soil builds. Pioneer species Moss Lichen Primary succession Exposed rock
Section 3.1 Summary – pages 65-69 Primary succession • After some time, primary succession slows down and the community becomes fairly stable, or reaches equilibrium.
Section 3.1 Summary – pages 65-69 Primary succession • A stable, mature community that undergoes little or no change in species is a climax community. Secondary succession Climax community
Section 3.1 Summary – pages 65-69 Secondary succession • Secondary succession is the sequence of changes that takes place after an existing community is severely disrupted in some way. • Secondary succession, however, occurs in areas that previously contained life, and on land that still contains soil.
Section 3.1 Summary – pages 65-69 Secondary succession • Because soil already exists, secondary succession may take less time than primary succession to reach a climax community.
Section 3.1 Summary – pages 65-69 Formation of Climax Community
Section 1 Check Question 1 A(n) _____ is something that restricts the existence, numbers, reproduction or distribution of organisms. A. abiotic factor B. biotic factor C. tolerance factor D. limiting factor FL: SC.G.2.4.5
Section 1 Check Common Limiting Factors The answer is D. A limiting factor may be a abiotic factor. Tolerance refers to an organism’s ability to withstand fluctuations of environmental factors. Sunlight Climate Atmospheric gases Temperature Water Nutrients/Food Fire Soil chemistry Space Other organisms FL: SC.G.2.4.5
Section 1 Check Question 2 Which of the following best illustrates primary succession? A. lichen growing on a lava bed B. wildflowers growing where forest fires had burned C. pine seedlings sprouting D. mature trees growing
Section 1 Check The answer is A. Primary succession is the colonization of barren land by pioneer species, such as moss or lichens.
Section 1 Check Question 3 What is required in order for secondary succession to occur? FL: SC.G.2.4.2
Section 1 Check Secondary succession occurs in areas that previously contained life. Soil must be present on this land, and the species that grow will differ from pioneer species. FL: SC.G.2.4.2
Section 1 Check Question 4 A stable, mature community that undergoes little or no change in species is a(n) _____. A. photic zone B. primary community C. climax community D. estuary
Section 1 Check The answer is C. Even though a climax community is stable, balanced change continues. Secondary succession Climax community
3.2 Section Objectives – page 70 Section Objectives: • Compare and contrast the photic and aphotic zones of marine biomes. • Identify the major limiting factors affecting distribution of terrestrial biomes. • Distinguish among biomes.
Section 3.2 Summary – pages 70-83 What is a biome? • A biome is a large group of ecosystems that share the same type of climax community. • There are terrestrial biomes and aquatic biomes, each with organisms adapted to the conditions characteristic of the biome.
Section 3.2 Summary – pages 70-83 What is a biome? • Biomes located on land are called terrestrial biomes. • Oceans, lakes, streams, ponds, or other bodies of water are aquatic biomes.
Section 3.2 Summary – pages 70-83 Aquatic Biomes • Approximately 75 percent of Earth’s surface is covered with water. • Most of that water is salty. • Freshwater is confined to rivers, streams, ponds, and most lakes. • As a result, aquatic biomes are separated into marine biomes and freshwater biomes.
Section 3.2 Summary – pages 70-83 Marine biomes • Different parts of the ocean differ in biotic and abiotic factors (salinity, depth, availability of light, and temperature) found there. • One of the ways ecologists study marine biomes is to make separate observations in shallow, sunlit zones and deeper, unlighted zones.
Section 3.2 Summary – pages 70-83 Marine biomes • The portion of the marine biome that is shallow enough for sunlight to penetrate is called the photic zone.
Section 3.2 Summary – pages 70-83 Marine biomes • Deeper water that never receives sunlight makes up the aphotic zone.
Section 3.2 Summary – pages 70-83 Estuaries—Mixed waters • An estuary is a coastal body of water, partially surrounded by land, in which freshwater and salt water mix. • The salinity, or amount of salt, in an estuary ranges between that of seawater and that of freshwater, and depends on how much freshwater the river brings into the estuary.
Section 3.2 Summary – pages 70-83 Estuaries—Mixed waters • Estuaries, may contain salt marsh ecosystems, which are dominated by salt-tolerant smooth cordgrass, salt marsh hay, or eelgrasses.
Section 3.2 Summary – pages 70-83 The effects of tides • Daily, the gravitational pull of the sun and moon causes the rise and fall of ocean tides. • The portion of the shoreline that lies between the high and low tide lines is called the intertidal zone. • Intertidal ecosystems have high levels of sunlight, nutrients, and oxygen.
Section 3.2 Summary – pages 70-83 The effects of tides • Intertidal zones differ in rockiness and wave action. • If the shore is rocky, waves constantly threaten to wash organisms into deeper water.
Section 3.2 Summary – pages 70-83 The effects of tides • If the shore is sandy, wave action keeps the bottom in constant motion.
Section 3.2 Summary – pages 70-83 In the light • The photic zone of the marine biome includes the vast expanse of open ocean that covers most of Earth’s surface. • Most of the organisms that live in the marine biome are plankton.
Section 3.2 Summary – pages 70-83 In the light • Plankton are small organisms that drift and float in the waters of the photic zone.