1 Introduction to the Study of Life Bio 103 Lecture GMU Dr. Largen 2 Outline Biology is the science of life The process of science Evolution, unity and diversity Core principles of biology 3 The Science of Biology Life s characteristics and levels of organization define the scope of biology 4 The Science of Biology Definitions of biology Webster s Ninth Collegiate Dictionary a branch of knowledge that deals with living organisms and vital processes the plant and animal life of a region or environment the life processes of an organism or group 5 The Science of Biology Definitions of biology New York Public Library Science Desk Reference the science of life the study of living systems same as textbook definitions 6 The Science of Biology non-living (and living) within cells, single celled organisms within multicellular organisms among organisms 7 The Science of Biology
non-living (and living) atom molecule within cells macromolecule (biological) organelle cell 8 The Science of Biology within multicellular organisms tissue organ organ systems 9 The Science of Biology among organisms species population community ecosystem biosphere ecosphere 10 The Science of Biology these levels represent a hierarchy» each level is built of parts at successively lower levels of organization 11 Figure 1.2 The hierarchy of biological organization (Biology, 6th Ed., Campbell & Reece) 12 13 The Science of Biology Life s levels of organization Question: Which of the following levels of biological organization includes all others of the list? cell molecule organ tissue 14 The Science of Biology Life s levels of organization Question: Which of the following levels of biological organization includes all others of the list?
cell molecule organ tissue 15 The Science of Biology 16 Structure and function are correlated at all levels of biological organization How something works is correlated with its structure form fits function. Analyzing a biological structure gives us clues about what it does how it works. Alternatively, knowing function of structure provides insight into its construction. structure-function relationship clear in aerodynamic efficiency in shape of bird wing. 17 Figure 1.6 Form fits function (Biology, 6th Ed., Campbell & Reece) 18 The Science of Biology What makes something alive? List some characteristics 19 The Science of Biology What is life? What qualifies something as "living"? All living organisms share five basic characteristics order sensitivity (response to environment) growth, development, reproduction regulation & homeostasis evolutionary adaptation 20 Figure 1.3 Some properties of life (Biology, 6th Ed., Campbell & Reece) 21 The Science of Biology Basic characteristics of life 22 Figure 1.3ax Order order all organisms consist of one or more cells examples illustrated on next slide 23 The Science of Biology Basic characteristics of life
sensitivity (response to environment) all organisms respond to stimuli 24 The Science of Biology Basic characteristics of life reproduction 25 Figure 1.3bx Reproduction organisms reproduce their own kind life comes only from life biogenesis examples illustrated on next slide 26 The Science of Biology Basic characteristics of life growth & development all living organisms are capable of using energy examples illustrated on next slide 27 Figure 1.3cx Growth and development 28 The Science of Biology Basic characteristics of life energy utilization organisms take in energy and transform it to do many kinds of work examples illustrated on next slide 29 Figure 1.3dx Energy utilization 30 The Science of Biology Basic characteristics of life regulation & homeostasis all organisms have regulatory mechanisms that coordinate internal processes maintain relatively constant internal conditions, different from their environment 31 Figure 1.8 Regulation by feedback mechanisms (Biology, 6th Ed., Campbell & Reece) 32 The Science of Biology Basic characteristics of life evolutionary adaptation life evolves as a result of interaction between organisms and their environments 33 Outline Biology is the science of life The Process of Science Evolution, unity and diversity Core principles of biology 34 The Process of Science Scientific thinking employs two types of reasoning
deductive reasoning uses general principles to predict specific results inductive reasoning uses specific observations to construct general scientific principles 35 The Process of Science Scientists pose and test hypotheses to answer questions about nature the process of science can be viewed as a five step process observations questions hypotheses predictions tests 36 The Process of Science Scientists pose and test hypotheses to answer questions about nature observations can come from others or results of earlier tests resulting in the raising of a question 37 The Process of Science Scientists pose and test hypotheses to answer questions about nature questions about unclear aspects of the observations: how? why? when? leads to the development of an hypothesis 38 The Process of Science Scientists pose and test hypotheses to answer questions about nature hypotheses tentative explanations of a phenomenon phrased in such a way as to be testable used to develop predictions 39 The Process of Science Scientists pose and test hypotheses to answer questions about nature predictions logical, testable outcomes of hypotheses developed using deductive reasoning take the form of» if (statement of hypothesis) is true, then (predictions) 40 The Process of Science Scientists pose and test hypotheses to answer questions about nature tests to determine if predictions are supported (fail to falsify) or falsified
experiments which test hypothesis have certain important components 41 The Process of Science tests - consist of plan experiments to test hypothesis perform experiments collect data analyze and interpret data determine if data support hypothesis: accept, reject or modify hypothesis carry out additional testing share data with other scientists if predictions are confirmed by scientific community, idea may become a theory 42 The Process of Science process of science will not prove a hypothesis true results support or falsify hypothesis 43 Figure 1.19 Idealized version of the scientific method (Biology, 6th Ed., Campbell & Reece) 44 45 The Process of Science Theories much broader in scope than hypotheses have greater explanatory power than hypotheses 46 The Process of Science test hypothesis by performing experiment to see whether or not results are as predicted. Deductive logic takes form of If then logic 47 Figure 1.20 Applying hypothetico-deductive reasoning to a campground problem (Biology, 6th Ed., Campbell & Reece) 48 Outline Biology is the science of life The Process of Science Evolution, unity and diversity Core principles of biology 49 Evolution, Unity and Diversity The diversity of life can be arranged into three domains 50 Evolution, Unity and Diversity earliest classification schemes, two broad groups animal kingdom plant kingdom scientists learned more about significant differences among living organisms adopted classification system that recognizes a taxonomic level higher than kingdom domain 51 Evolution, Unity and Diversity
All life can be classified into one of the three domains Archaea Bacteria Eukarya 52 Evolution, Unity and Diversity 53 54 Domain Archaea single-celled, ancient bacteria Domain Bacteria single-celled, true bacteria Domain Eukarya single-celled protists, paramecia, single- and multi-cellular algae fungi plants animals 55 Evolution, Unity and Diversity 56 How many kingdoms of life? most biologists now use a six-kingdom classification system first proposed by Carl Woese of the University of Illinois all life currently classified into 6 kingdoms Archaebacteria Eubacteria Protista Fungi Plantae Animalia 57 Figure 1.11 Three domains of life (Biology, 6th Ed., Campbell & Reece) 58 Figure 1.10 Classifying life (Biology, 6th Ed., Campbell & Reece) 59 Evolution, Unity and Diversity 60 Domain Archaea Kingdom Archaebcateria Domain Bacteria Kingdom Eubacteria Domain Eukarya Kingdom Protista Kingdom Fungi Kingdom Plantae Kingdom Animalia 61 Evolution, Unity and Diversity Prokaryotic kingdoms
Archaebacteria Eubacteria Eukaryotic kingdoms Protista Fungi Plantae Animalia 62 Evolution, Unity and Diversity Unity in diversity All forms of life have common features Life is diverse, but there are common themes that all living things exhibit 63 64 Underlying the diversity of life is a striking unity. universal genetic language of DNA unites prokaryotes, like bacteria, with eukaryotes, like humans. Among eukaryotes, unity is evident in many details of cell structure. 65 Evolution, Unity and Diversity Living organisms and their environments form interconnecting webs living organisms do not exist in isolation organism s environment includes both living and non-living components 66 Evolution, Unity and Diversity Living organisms and their environments form interconnecting webs photosynthetic organisms make food from carbon dioxide, water and energy of sun all animals ultimately depend on these photosynthetic organisms for food decomposers help recycle organic matter back to photosynthetic organisms 67 Evolution, Unity and Diversity Living organisms and their environments form interconnecting webs 68 Outline relationships among the living and non-living components of an ecosystem can be illustrated as a web The scope of biology The process of science Evolution, unity and diversity Core principles of biology 69 Core principles of biology
Biology is is a broad collection of subthemes how do biologists organize their subject matter? By identifying common concepts that underlie all life, and therefore, all biological study 70 Core principles of biology Biology is is a broad collection of subthemes cell biology genetics organismal biology evolution ecology 71 Core principles of biology Biology is connected to our lives in many ways birth and death; human population; nutrition, exercise and dieting; medical concerns of all kinds; agriculture and forestry; biodiversity and endangered species; pollution and environmental change; energy. 72 Core principles of biology biology is most encompassing of all sciences partly because living systems are so complex biology is an multidisciplinary science that requires a knowledge of chemistry, physics, and mathematics. 73 Core principles of biology 74 75 76 77 Biology is also the science most connected to humanities and social sciences. complexity of life is inspiring, but it can be overwhelming. Ten themes cut across all biological fields.