Transcript Ch 1 Notes
Chapter 1 The Study of Life Lecture Outline See PowerPoint Image Slides for all figures and tables pre-inserted into PowerPoint without notes. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. monarch butterfly feeding on nectar Masai giraffes giant sequoia planet Earth mushroom on northern forest floor humans in a city male peacock displaying feathers (sequoia): © Robert Glusic/Getty RF; (mushroom): © IT Stock/Age Fotostock RF; (peacock): © Brand X Pictures/PunchStock RF; (humans): © Heath Korvola/UpperCut Images/Getty RF; (giraffes): © Dr. Sylvia S. Mader; (butterfly): © Creatas/PunchStock RF; (Earth): © Ingram Publishing/Alamy RF 1.1 The Characteristics of Life • Life exists almost everywhere on the planet Earth. • Earth possesses a great variety of diverse life forms. • All living things have certain characteristics in common. Living Things: • • • • • • • Are organized Acquire materials and energy Reproduce Respond to stimuli Are homeostatic Grow and develop Have the capacity to adapt Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. • Living things are organized in a hierarchy of levels. • A cell is the smallest unit of life. • A tissue is a group of similar cells that perform a particular function. • Several tissues join together to form an organ. • Organs work together to form an organ system. Organisms human tree Organ Systems organ system Organs leaf brain Tissues leaf tissues nerve tissue plant cell nerve cell Cells DNA molecule Molecules Atoms • Living things need an outside source of materials and energy to maintain their organization and carry on life’s other activities. • Energy – capacity to do work • Growth – increase is size or number of cells • Development – changes that take place from conception to death 1.2 The Classification of Living Things • Living organisms are assigned to groups based upon their similarities. • Systematics is the discipline of identifying and classifying organisms. Domains • Domains are the largest classification category. • Biologists assign organisms to one of three domains based on biochemical and genetic evidence. • Prokaryotes lack a membrane-bounded nucleus. • Eukaryotes have a membrane-bounded nucleus. Domain Archaea • Archaea are unicellular prokaryotes. • Archaea can be found in environments that are too hostile for other life forms. Domain Bacteria • Bacteria are unicellular prokaryotes. • Bacteria are found almost everywhere on the planet Earth. • Some bacteria cause disease but many are beneficial. Domain Eukarya • The cells of all eukaryotes have a membranebound nucleus. • Members of the Domain Eukarya are further categorized into one of four Kingdoms. • Kingdom Protista – may be several kingdoms • Kingdom Fungi • Kingdom Plantae • Kingdom Animalia Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. DOMAIN EUKARYA Kingdom Protista Organization Type of Nutrition Complex single cell, some multicellular Absorb, photosynthesize, or ingest food Representative Organisms Protozoans, algae, water molds, and slime molds paramecium Fungi Some unicellular, most multicellular filamentous forms with specialized complex cells euglenoid Multicellular form with specialized complex cells Molds, yeasts, and mushrooms Multicellular form with specialized complex cells yeast mushroom bracket fungus Photosynthesize food moss Animalia dinoflagellate Absorb food black bread mold Plantae slime mold fern pine tree nonwoody flowering plant Invertebrates, fishes, reptiles, amphibians, birds, and mammals Ingest food sea star c. Eukaryotes are divided into four kingdoms. Mosses, ferns, nonwoody and woody flowering plants earthworm finch raccoon Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. DOMAIN ARCHAEA DOMAIN BACTERIA Methanosarcina mazei a. Archaea are capable of living in extreme environments. Escherichia coli b. Bacteria are found nearly everywhere. 1.6 m 1.5 m DOMAIN EUKARYA Kingdom Protista Organization Type of Nutrition Complex single cell, some multicellular Absorb, photosynthesize, or ingest food Representative Organisms Protozoans, algae, water molds, and slime molds paramecium Fungi Some unicellular, most multicellular filamentous forms with specialized complex cells euglenoid Multicellular form with specialized complex cells Molds, yeasts, and mushrooms Multicellular form with specialized complex cells yeast mushroom bracket fungus Photosynthesize food moss Animalia dinoflagellate Absorb food black bread mold Plantae slime mold fern pine tree nonwoody flowering plant Mosses, ferns, nonwoody and woody flowering plants Invertebrates, fishes, reptiles, amphibians, birds, and mammals Ingest food sea star earthworm finch raccoon c. Eukaryotes are divided into four kingdoms. (bacteria): © A.B. Dowsett/SPL/Photo Researchers, Inc.; (archaean): © Ralph Robinson/Visuals Unlimited Categories of Classification Domain Kingdom Phylum Class Order Family Genus Species Most inclusive Least inclusive Categories of Classification Scientific Names • Taxonomy is the assignment of a binomial to each species. • Binomial (two name) – Genus name, species name – Genus capitalized, both words in italics –Examples: »Homo sapiens »Pisum sativum »Felis domesticus 1.3 The Organization of the Biosphere • Biosphere – The zone of air, land, and water at the surface of the Earth where living organisms are found. • Population – All the members of a species within a particular area • Community – All the different populations in the same area 1.3 The Organization of the Biosphere • Ecosystem – Community interact among themselves and with the physical environment (soil, atmosphere, etc.) – Characterized by • Chemical cycling – chemicals move from 1 species to another • Energy flow – energy flows from the sun, through plants, through the food chain Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. heat solar energy heat heat heat heat heat WASTE MATERIAL,DEATH, AND DECOMPOSITION Chemical cycling Energy flow • Climate largely determines where different ecosystems are found around the globe • The two most biologically diverse ecosystems— tropical rain forests and coral reefs—occur where solar energy is most abundant. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. great barracuda attached algae white shark green moray yellowtail snapper yellow jack Spanish hogfish foureye butterfly fish corals bar jack queen angelfish sponges parrotfish Bermuda chub surgeonfish yellowtail damselfish sea grass sea urchin spiny lobster phytoplankton sea star zooplankton detritus The Human Species • The human species tends to modify existing ecosystems for its own purposes. • Tropical rain forests and coral reefs are severely threatened as global human population increases. • Human begins depends on healthy ecosystems for food, medicine, and raw materials. Biodiversity • Ecompasses – Total number of species – The variability in their genes – The ecosystems in which they live • As many as 5-30 million species on Earth • Human activities cause the extinction of about 400 species per day. 1.4 The Process of Science • Biology is the scientific study of life. • Biologists—and all scientists—generally test hypotheses using the scientific method. 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. Conclusion The results are analyzed, and the hypothesis is supported or rejected. Scientific Theory Many experiments and observations support a theory. Courtesy Leica Microsystems, Inc. The Process of Science • Inductive reasoning occurs whenever a person uses creative thinking to combine isolated f – A scientist comes up with a hypothesis, a tentative explanation for the natural event. acts into a cohesive whole. • To determine how to test a hypothesis, a scientist uses deductive reasoning. – Involves “if, then” logic Scientific theory • Concepts that join together well-supported and related hypotheses. • In science, a theory is supported by a broad range of observations, experiments, and data. – Examples – Cell , homeostasis, gene, ecosystem, and evolution • The theory of evolution is the unifying concept of biology. A Controlled Study • Experiments in controlled studies have two types of groups: • Control Group – receives no treatment • Experimental Group – receives treatment The Experiment • HYPOTHESIS: A pigeon pea/winter wheat rotation will cause winter wheat production to increase as well as or better than the use of nitrogen fertilizer. • PREDICTION: Wheat production (biomass) following the growth of pigeon peas will surpass wheat biomass following nitrogen fertilizer treatment. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Control pot Test pot Test pot no fertilization treatment 90 kg of nitrogen/ha Pigeon pea/winter wheat rotation a. Control pot and three types of test pots Test pot 45 kg of nitrogen/ha Courtesy Jim Bidlack • Control – no fertilization treatment • Tests – Winter wheat in soil treated with nitrogen fertilizer (45kg/ha) – Winter wheat in soil treated with nitrogen fertilizer (90kg/ha) – Pigeon pea plants tilled into soil and then winter wheat planted • All other conditions the same in all pots Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Wheat Biomass (grams/pot) 20 Control Pots = no fertilization treatment 15 Test Pots = 45 kg of nitrogen/ha = 90 kg of nitrogen/ha = Pigeon pea/winter wheat rotation 10 5 0 year 1 b. Results year 2 year 3 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Control pot Test pot Test pot no fertilization treatment 90 kg of nitrogen/ha Pigeon pea/winter wheat rotation 20 a. Control pot and three types of test pots Test pot 45 kg of nitrogen/ha Wheat Biomass (grams/pot) Control Pots = no fertilization treatment 15 Test Pots = 45 kg of nitrogen/ha = 90 kg of nitrogen/ha = Pigeon pea/winter wheat rotation 10 5 0 year 1 b. Results Courtesy Jim Bidlack year 2 year 3 The Experiment • Conclusion: The hypothesis was supported. At the end of two years, the yield of winter wheat following a pigeon pea/winter wheat rotation was better than for the other type pots. 1.5 Science and Social Responsibility • Technology is the application of knowledge for a practical purpose. • Technology has both benefits and drawbacks. • Ethical and moral issues surrounding the use of technology must be decided by everyone. – Responsibility for how to use scientific technology must reside with people from all walks of life, not with scientists alone