1 Biology Sylvia S. Mader Michael Windelspecht Chapter 1 A View of Life Lecture Outline Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. See separate FlexArt PowerPoint slides for all figures and tables pre-inserted into PowerPoint without notes.

1.1 How to Define Life Biology is the scientific study of life. There is great diversity among living things. Living things:  are composed of the same chemical elements as nonliving things.  obey the same physical and chemical laws that govern everything in the universe. 2

Diversity of Life 3 Despite diversity, all living things share the same basic characteristics.

Characteristics of Life 1. Living things are organized. The levels of biological organization range from atoms to the biosphere. The cell is the basic unit of structure and function of all living things.  Unicellular or multicellular Each level of organization is more complex than the level preceding it.  As biological complexity increases, each level acquires new emergent properties. 4

Atom Smallest unit of an element composed of electrons, protons, and neutrons Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. oxygen Levels of Biological Organization

Atom Smallest unit of an element composed of electrons, protons, and neutrons Molecule Union of two or more atoms of the same or different elements Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. oxygen methane

Atom Smallest unit of an element composed of electrons, protons, and neutrons Molecule Union of two or more atoms of the same or different elements Cell The structural and functional unit of all living things Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. oxygen methane plant cellnerve cell

Atom Smallest unit of an element composed of electrons, protons, and neutrons Molecule Union of two or more atoms of the same or different elements Cell The structural and functional unit of all living things Tissue A group of cells with a common structure and function Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. oxygen methane plant cell epidermal tissue nerve cell nervous tissue

Atom Smallest unit of an element composed of electrons, protons, and neutrons Molecule Union of two or more atoms of the same or different elements Cell The structural and functional unit of all living things Tissue A group of cells with a common structure and function Organ Composed of tissues functioning together for a specific task Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. oxygen methane plant cell epidermal tissue nerve cell nervous tissue leaves the brain

Atom Smallest unit of an element composed of electrons, protons, and neutrons Molecule Union of two or more atoms of the same or different elements Cell The structural and functional unit of all living things Tissue A group of cells with a common structure and function Organ Composed of tissues functioning together for a specific task Organ System Composed of several organs working together Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. oxygen methane plant cell epidermal tissue nerve cell nervous tissue leaves the brain shoot system nervous system

Atom Smallest unit of an element composed of electrons, protons, and neutrons Molecule Union of two or more atoms of the same or different elements Cell The structural and functional unit of all living things Tissue A group of cells with a common structure and function Organ Composed of tissues functioning together for a specific task Organ System Composed of several organs working together Organism An individual; complex individuals contain organ systems Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. oxygen methane plant cell epidermal tissue nerve cell nervous tissue leaves the brain shoot system nervous system tree elephant

Atom Smallest unit of an element composed of electrons, protons, and neutrons Molecule Union of two or more atoms of the same or different elements Cell The structural and functional unit of all living things Tissue A group of cells with a common structure and function Organ Composed of tissues functioning together for a specific task Organ System Composed of several organs working together Organism An individual; complex individuals contain organ systems Population Organisms of the same species in a particular area Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. oxygen methane plant cell epidermal tissue nerve cell nervous tissue leavesthe brain shoot system nervous system tree elephant

Atom Smallest unit of an element composed of electrons, protons, and neutrons Molecule Union of two or more atoms of the same or different elements Cell The structural and functional unit of all living things Tissue A group of cells with a common structure and function Organ Composed of tissues functioning together for a specific task Organ System Composed of several organs working together Organism An individual; complex individuals contain organ systems Population Organisms of the same species in a particular area Community Interacting populations in a particular area Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. oxygen methane plant cell epidermal tissue nerve cell nervous tissue leaves the brain shoot system nervous system tree elephant

Atom Smallest unit of an element composed of electrons, protons, and neutrons Molecule Union of two or more atoms of the same or different elements Cell The structural and functional unit of all living things Tissue A group of cells with a common structure and function Organ Composed of tissues functioning together for a specific task Organ System Composed of several organs working together Organism An individual; complex individuals contain organ systems Population Organisms of the same species in a particular area Community Interacting populations in a particular area Ecosystem A community plus the physical environment Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. oxygen methane plant cell epidermal tissue nerve cell nervous tissue leaves the brain shoot system nervous system treeelephant

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Biosphere Regions of the Earth’s crust, waters, and atmosphere inhabited by living things Ecosystem A community plus the physical environment Community Interacting populations in a particular area Population Organisms of the same species in a particular area Organism An individual; complex individuals contain organ systems Organ System Composed of several organs working together Organ Composed of tissues functioning together for a specific task Tissue A group of cells with a common structure and function Cell The structural and functional unit of all living things Molecule Union of two or more atoms of the same or different elements Atom Smallest unit of an element composed of electrons, protons, and neutrons oxygen methane plant cell epidermal tissue nerve cell nervous tissue leaves the brain shoot system nervous system treeelephant

Characteristics of Life 2. Living things acquire materials and energy. Energy is the ability to do work.  Energy is required to maintain organization and conduct life-sustaining processes such as chemical reactions. Metabolism is all the chemical reactions that occur in a cell.  The sun is the ultimate source of energy for nearly all life on Earth. Plants, algae, and some other organisms capture solar energy and perform photosynthesis. Photosynthesis is a process that converts solar energy into the chemical energy of carbohydrates. 16

Acquiring Nutrients and Energy 17 food Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. f. e. d. c. b. a. a: © John Warden/Purestock/SuperStock RF; b:© Photodisc Blue/Getty RF; c: © Charles Bush Photography; d : © Michael Abby/Visuals Unlimited; e: © Pat Pendarvis; f: National Park Service Photo

Characteristics of Life 3. Living things maintain homeostasis. Homeostasis is the maintenance of internal conditions within certain boundaries.  Ability to maintain a state of biological balance  Feedback systems monitor internal conditions and make adjustments Living things respond to stimuli. Living things interact with the environment and respond to changes in the environment.  The ability to respond often produces movement.

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Characteristics of Life 5. Living things reproduce and develop. All living organisms must reproduce to maintain a population. The manner of reproduction varies among different organisms. When organisms reproduce, they pass on copies of their genetic information (genes) to the next generation.  Genes determine the characteristics of an organism.  Genes are composed of DNA (deoxyribonucleic acid). 20

Characteristics of Life 6. Living things have adaptations. An adaptation is any modification that makes an organism better able to function in a particular environment. The diversity of life exists because over long periods of time, organisms respond to changing environments by developing new adaptations. Evolution is the change in a population of organisms over time to become more suited to the environment. 21

1.2 Evolution, the Unifying Concept of Biology The theory of evolution explains the diversity and unity of life.  The theory of evolution suggests how all living things descended from a common ancestor.  Common descent with modification 22

Evolutionary Tree of Life 23 An evolutionary tree is like a family tree. An evolutionary tree traces the ancestry of life on Earth to a common ancestor.

common ancestor (first cells) Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

common ancestor (first cells) BACTERIA ARCHAEA Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

common ancestor (first cells) BACTERIA ARCHAEA cell with nucleus EUKARYA Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

common ancestor (first cells) BACTERIA ARCHAEA Protists cell with nucleus EUKARYA Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

common ancestor (first cells) BACTERIA ARCHAEA Protists Plants Fungi Animals cell with nucleus EUKARYA Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

common ancestor (first cells) BACTERIA ARCHAEA Protists Plants Fungi Animals Present Time Past cell with nucleus EUKARYA Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Organizing Diversity Taxonomy is the branch of biology that identifies, names, and classifies organisms. Systematics is the study of evolutionary relationships between organisms. Classification categories  From least inclusive category (species) to most inclusive category (domain): Species, genus, family, order, class, phylum, kingdom, and domain Each successive category above species includes more types of organisms than the preceding one. 30

Levels of Classification

Domains Domain Archaea  Contains unicellular prokaryotes that live in extreme environments Prokaryotes lack a membrane-bound nucleus. Domain Bacteria  Contains unicellular prokaryotes that live in all environments Domain Eukarya  Contains unicellular and multicellular eukaryotes Eukaryotes contain a membrane-bound nucleus. 32

Domain Archaea 33 Methanosarcina mazei, an archaean 1.6 m Prokaryotic cells of various shapes Adaptations to extreme environments Absorb or chemosynthesize food Unique chemical characteristics Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. © Ralph Robinson/Visuals Unlimited

Domain Bacteria 34 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Prokaryotic cells of various shapes Adaptations to all environments Absorb, photosynthesize, or chemosynthesize food Unique chemical characteristics Escherichia coli, a bacterium1.5m © A.B. Dowsett/SPL/Photo Researchers, Inc.

Fig. 1.8 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Passiflora, passion flower, a flowering plant Domain Eukarya: Protists Algae, protozoans, slime molds, and water molds Complex single cell (sometimes filaments, colonies, or even multicellular) Absorb, photosynthesize, or ingest food Paramecium, a unicellular protozoan 1 µm Domain Eukarya: Kingdom Fungi Molds, mushrooms, yeasts, and ringworms Mostly multicellular filaments with specialized, complex cells Absorb food Amanita, a mushroom Domain Eukarya: Kingdom Plantae Certain algae, mosses, ferns, conifers, and flowering plants Multicellular, usually with specialized tissues, containing complex cells Domain Eukarya: Kingdom Animalia Sponges, worms, insects, fishes, frogs, turtles, birds, and mammals Multicellular with specialized tissues containing complex cells Ingest food Vulpes, a red fox Photosynthe size food a: © Michael Abby/Visuals Unlimited; b: © Pat Pendarvis; c: © Tinke Hamming/Ingram Publishing RF; d: © Corbis RF Domain Eukarya

Kingdoms Domain Archaea – kingdom designations undetermined Domain Bacteria - kingdom designations undetermined Domain Eukarya  Protists (composed of several kingdoms)  Kingdom Fungi  Kingdom Plantae  Kingdom Animalia 36

Scientific Names Universal Latin-based Binomial nomenclature  Two-part name  First word is the genus. Always capitalized  Second word is the species designation (or specific epithet). Written in lowercase  Both words are italicized.  Examples: Homo sapiens (humans), Zea mays (corn) 37

38 Natural Selection Evolutionary mechanism proposed by Charles Darwin Some aspect of the environment selects which traits are more apt to be passed on to the next generation.  Individuals with the favorable traits produce the greater number of offspring that survive and reproduce.  Increases the frequency of those traits in population Mutations fuel natural selection.  Introduce variations among members of a population

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Some plants within a population exhibit variation in leaf structure. Deer prefer a diet of smooth leaves over hairy leaves. Plants with hairy leaves reproduce more than other plants in the population. Generations later, most plants within the population have hairy leaves, as smooth leaves are selected against.

1.3 How the Biosphere Is Organized The biosphere is the zone of air, land, and water where organisms exist. A population is all the members of a species within an area. A community is a collection of interacting populations within the same environment. An ecosystem is community plus its physical environment. 40

Ecosystems Ecosystems are characterized by chemical cycling and energy flow.  Chemicals are not used up when organisms die. Chemicals move from one population to another in a food chain. As a result of death and decomposition, chemicals are returned to living plants.  Energy from the sun flows through plants and other members of the food chain as one population feeds on another. Therefore, there must be a constant input of solar energy. 41

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. WASTE MATERIAL, DEATH, AND DECOMPOSITION heat solar energy Chemical cycling Energy flow heat Chemicals Cycle and Energy Flows

The Human Population Ecosystems have been negatively impacted by human populations.  Destruction of forest or grassland for agriculture, housing, industry  Destruction of coastal wetlands by waste and other pollutants Humans depend upon healthy ecosystems for:  Food  Medicines  Raw materials 43

The Effect of Human Activities on Coral Reefs Minimal coral death b. a. Healthy coral reef 1985 Some coral death With no fish present 1995 Coral bleaching with limited chance of recovery 2004 Coral is black from sedimentation; bleaching still evident Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. a: © Frank & Joyce Burek/Getty Images; b (All): © Dr. Phillip Dustan

Biodiversity Biodiversity is the total number and relative abundance of species, the variability of their genes, and the ecosystems in which they live.  Estimated to be as high as 15 million species Less than 2 million have been named and identified Extinction is the death of the last member of a species or larger classification category.  Estimates of 400 species/day lost due to human activities 45

1.4 The Process of Science The scientific method is a standard series of steps used in gaining new knowledge through research.  The scientific method can be divided into four steps: Observation Hypothesis Experiments and Data Collection Conclusion 46

The Scientific Method 1. Observation Scientists use their senses to gather information about a phenomenon or natural event. 2. Hypothesis A hypothesis is a tentative explanation for what was observed. Developed through inductive reasoning Testable 47

The Scientific Method 3. Experiments and Data Collection An experiment is a series of procedures designed to test a hypothesis.  Utilizes deductive reasoning to make a prediction or expected outcome The manner in which a scientist conducts an experiment is called the experimental design.  A good experimental design ensures that the scientist is examining the contribution of a specific factor called the experimental (independent) variable to the observation. The experimental variable is the factor being tested. 48

The Scientific Method 3. Experiments and Data Collection (cont’d) A test group is exposed to the experimental variable. A control group goes through all aspects of the experiment but is not exposed to the experimental variable. The data are the results of an experiment.  Should be observable and objective 49

The Scientific Method 4. Conclusion The data are analyzed and interpreted to determine whether the hypothesis is supported or not.  If prediction happens, hypothesis is supported.  If not, hypothesis is rejected. Findings are reported in scientific journals Peers review the findings Other scientists then attempt to duplicate or dismiss the published findings 50

Observation New observations are made, and previous data are studied. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Flow Diagram of Scientific Method

Observation New observations are made, and previous data are studied. Hypothesis Input from various sources is used to formulate a testable statement. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

Observation New observations are made, and previous data are studied. Hypothesis Input from various sources is used to formulate a testable statement. Experiment/Observations The hypothesis is tested by experiment or further observations. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Courtesy Leica Microsystems Inc.

Observation New observations are made, and previous data are studied. Hypothesis Input from various sources is used to formulate a testable statement. Conclusion The results are analyzed, and the hypothesis is supported or rejected. Experiment/Observations The hypothesis is tested by experiment or further observations. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Courtesy Leica Microsystems Inc.

Observation New observations are made, and previous data are studied. Hypothesis Input from various sources is used to formulate a testable statement. Conclusion The results are analyzed, and the hypothesis is supported or rejected. Scientific Theory Many experiments and observations support a theory. Experiment/Observations The hypothesis is tested by experiment or further observations. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Courtesy Leica Microsystems Inc.

Observation New observations are made, and previous data are studied. Hypothesis Input from various sources is used to formulate a testable statement. Conclusion The results are analyzed, and the hypothesis is supported or rejected. Scientific Theory Many experiments and observations support a theory. Experiment/Observations The hypothesis is tested by experiment or further observations. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Courtesy Leica Microsystems Inc.

Scientific Theory Scientific Theory:  Concepts that join together two or more well-supported and related hypotheses  Supported by broad range of observations, experiments, and data Scientific Principle / Law:  Widely accepted set of theories  No serious challenges to validity 57

58 Basic Theories of Biology

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. = Pigeon pea/winter wheat rotation year 1year 2year 3 = no fertilization treatment = 45 kg of nitrogen/ha Control Pots Test Pots = 90 kg of nitrogen/ha Wheat Biomass (grams/pot) b. Results a. Control pots and test pots of three types Test pots 90 kg of nitrogen/ha Test pots Pigeon pea/winter wheat rotation Control pots no fertilization treatment Test pots 45 kg of nitrogen/ha (All): Courtesy Jim Bidlack Using the Scientific Method: Pigeon Pea/Winter Wheat Rotation Study

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. a. Scientist making observations b. Normal mountain bluebird nesting behavior c. Resident male attacking a male model near nest resident male female mate male bluebird model d. Observation of two experimental nests provided data for graph Approaches per Minute nest construction first egg laid hatching of eggs Stage of Nesting Cycle Approaches to male model Approaches to female mate nest 2 nest 1 © Erica S. Leeds Using the Scientific Method: A Field Study