General Biology I. For M117 and D76 Students. 陳正繹 Dept. of Biology & Anatomy National Defense Medical Cente

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1 General Biology I For M117 and D76 Students 陳正繹 Dept. of Biology & Anatomy National Defense Medical Cente

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3 Text Book USA Edition : Traditional Global Edition

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7 Chapter 1 Evolution, the Themes of Biology, and Scientific Inquiry 2017 Pearson Education, Inc. Lecture Presentations by Nicole Tunbridge and Kathleen Fitzpatrick

8 Chapter 1 Biology and Its Themes 2018 Pearson Education Ltd. Lecture Presentations by Nicole Tunbridge and Kathleen Fitzpatrick

9 1.0 Inquiring About Life An organisms adaptations to its environment are the result of evolution For example, the color of the beach mouse has come to be well matched, or adapted, to its local background Evolution 演化 is the process of change that has transformed life on Earth An inland mouse of the species Peromyscus polionotus What can this beach mouse teach us about biology?

10 Evolution 演化 is the process of change that has transformed life on Earth Biology 生物學 is the scientific study of life Biologists 生物學家 ask questions such as: 1. How a single cell develops into an organism. 2. How the human mind works. 3. How living things interact in communities Life defines a simple, one-sentence definition Life is recognized by what living things do 10

11 Order 秩序 Evolutionary adaptation 演化的適應 Response to the environment 對環境的反應 Regulation 調節 Energy processing 能量的形成 Growth and development 生長與發育 Reproduction 生殖 Some properties of life

12 Key Concepts 1.1 The Study of Life Reveals Unifying Themes 1.2 The Core Theme: Evolution accounts for the unity and diversity of life 1.3 In studying nature, scientists make observations and form and test hypotheses 1.4 Science benefits from a cooperative approach and diverse viewpoints

13 1.1 The Study of Life Reveals Unifying Themes. Biology is a subject of enormous scope There are five unifying themes Organization Information Energy and matter Interactions Evolution

14 A. Theme: New properties emerge at successive level of the biological organization Life can be studied at different levels from molecules to the entire living planet. This enormous range can be divided into different levels of biological organization Biosphere 生物圈 Ecosystems 生態系 Communities 群落 Populations 族群 Organisms 生物體 Organs 器官 Tissue 組織 Cell 細胞 Organelle 胞器 Molecular 分子 Atom 原子 Exploring level of biological organization: 14

15 1. Emergent properties a. Emergent properties 新穎特質 result from the arrangement and interaction of parts within a system b. Emergent properties characterize non-biological entities as well Ex., a functioning bicycle emerges only when all of the necessary parts connect in the correct way 15

16 c. Reductionism 化約主義, 簡化論 is the reduction of complex systems to simpler components that are more manageable to study Ex. studying the molecular structure of DNA helps us to understand the chemical basis of inheritance d. To explore emergent properties, biologists complement reductionism with systems biology, analysis of the interactions among the parts of a biological system. 16

17 2. Structure and Function At each level of the biological hierarchy 階層 we find a correlation between structure and function Hummingbirds

18 3. The Cell: An Organism s Basic Units of Structure and Function a. The cell is the lowest level of organization that can perform all activities required for life b. All cells are enclosed by a membrane, use DNA as their genetic information c. A eukaryotic cell 真核細胞 has membrane-enclosed organelles 膜性胞器, the largest of which is usually the nucleus d. By comparison, a prokaryotic cell 原核細胞 is simpler and usually smaller, and does not contain a nucleus or other membrane-enclosed organelles. Contrasting eukaryotic and prokaryotic cells in size and complexity 18

19 B. Theme: Life s Processes Involve the Expression and Transmission of Genetic Information Within cells, structures called chromosomes 染色體 contain genetic material in the form of DNA (deoxyribonucleic acid) A lung cell from a newt divides into two smaller cells that grow and divide again 19

20 1. DNA, the Genetic Material a. Each chromosome has one long DNA molecule with hundreds or thousands of genes b. Genes encode information for building the molecules synthesized within the cell c. Genes are the units of inheritance d. DNA controls the development and maintenance of organisms Inherited DNA directs development of an organism

21 e. Each DNA molecule is made up of two long chains arranged in a double helix f. Each link of a chain is one of four kinds of chemical building blocks called nucleotides 核苷酸. DNA: The genetic material 21

22 Figure 1.8 (b) How do lens cells make crystallin proteins? Crystallin gene (a) Lens cells are tightly packed with transparent proteins called crystallin. Lens cell DNA TRANSCRIPTION A C C A A A C C G A G T T G G T T T G G C T C A g. Genes control protein production indirectly h. DNA is transcribed into RNA then translated into a protein. i. Gene expression is the process of converting information from gene to cellular product mrna TRANSLATION Chain of amino acids PROTEIN FOLDING Protein U G G U U U G G C U C A Crystallin protein Gene expression: The transfer of information from a gene results in a functional protein

23 2. Genomics: Large-Scale Analysis of DNA Sequences. a. An organism s genome 基因體 is its entire set of genetic instructions. b. The human genome and those of many other organisms have been sequenced using DNA-sequencing machines. c. Genomics 基因體學 is the study of sets of genes within and between species d. Proteomics 蛋白質體學 is the study of sets of proteins and their properties. Entile sets of proteins encoded by the genome (known as proteomes) e. The genomics approach depends on: i. High-throughput technology 高通量科技, which yields enormous amounts of data. ii. Bioinformatics, 生物資訊 which is the use of computational tools to process a large volume of data. iii. Interdisciplinary research teams 跨學科的研究團隊 Biology as an information science 23

24 C. Theme: Life Requires the Transfer and Transformation of Energy and Matter The input of energy from the sun and the transformation of energy from one form to another make life possible The chemical energy generated by plants and other photosynthetic organisms (producers 生產者 ) is passed along to consumers 消費者 Consumers are organisms that feed on other organisms or their remains

25 When organisms use energy to perform work, some energy is lost to the surroundings as heat As a result, energy flows 能量流動 through an ecosystem, usually entering as light and exiting as heat Energy flow and chemical cycling

26 D. Theme: From Molecules 生態系 to Ecosystems, Interactions Are Important in Biological Systems Interactions between the components of the system ensure smooth integration of all the parts. This holds true equally well for components of an ecosystem and the molecules in a cell 1. Molecules: Interactions With in Organisms Interactions between components organs, tissues, cells, and molecules that make up living organisms are crucial to their smooth operation Cells are able to coordinate various chemical pathways through a mechanism called feedback 迴饋

27 Feedback mechanisms allow biological processes to self-regulate a. Negative feedback 負向迴饋 The most common form of regulation in living organisms, in which the response reduces the initial stimulus, the process that creates it slows and less of the product is produced

28 b. Positive feedback 正向迴饋 :means that as more of a product accumulates, the process that creates it speeds up and more of the product is produced Ex. Clotting of blood 28

29 2. Ecosystems: An Organism s Interactions with Other Organisms and the Physical Environment At the ecosystem level, each organism interacts continuously with other organisms, These interactions may be beneficial or harmful to one or both of the organisms Organisms also interact continuously with the physical factors in their environment, and the environment is affected by the organisms living there

30 Humans interact with our environment, sometimes with dire consequences Over the past 150 years, humans have greatly increased the burning of fossil fuels and the release of carbon dioxide (CO 2 ) into the atmosphere The resulting global warming is just one aspect of climate change Wind and precipitation patterns are also shifting Extreme weather events such as storms and droughts are occurring more often As habitats deteriorate, plant and animal species shift their ranges to more suitable locations Populations of many species are shrinking in size or even disappearing Threatened by global warming

31 1.2: The core theme: Evolution accounts for the unity and diversity of life Evolution is the one idea that makes logical sense of everything we know about living organisms The scientific explanation for both the unity 一致性 and diversity 多樣性 of organisms is evolution, the concept that living organisms are modified descendants of common ancestors An abundance of evidence supports the occurrence of evolution. Nothing in biology makes sense except in the light of evolution Theodosius Dobzhansky (Neo-Darwinism 新達爾文主義 ) 31

32 1. The Three Domains of Life a. Organisms are divided into three domains, named Bacteria 細菌域, Archaea 古細菌域, and Eukarya 真核生物域 b. Domain Bacteriaand domain Archaeacomprise the prokaryotes (Kingdom Monera 原核生物界 ) c. Domain Eukarya includes all eukaryotic organisms The domain Eukarya includes three multicellular kingdoms: i. Plantae 植物界, which produce their own food by photosynthesis ii. Fungi 真菌界, which absorb nutrients iii. Animalia 動物界 which ingest their food d. Other eukaryotic organisms were formerly grouped into a called Protists kingdom 原生生物界, though the recent trend has been to split the protists into several kingdoms

33 The three domains of life

34 2. Unity 一致性 in the diversity of life An universal genetic code Similarities of cell structure An example of unity underlying the diversity of life; the architecture of cilia( 纖毛 ) in eukaryotes 34

35 The history of life as documented by fossils and other evidence is the saga of a changing Earth, billions of years old Digging the past 35

36 B. Charles Darwin and the theory of natural selection 1.Charles Darwin published On the Origin of Species by Means of Natural Selection in 1859 Darwin made two main points: Species showed evidence of descent with modification 修飾的後裔 from common ancestors 共通祖先 Natural selection 天擇 is the mechanism behind descent with modification Charles Darwin as a young man

37 2. Darwin s theory explained the duality of unity 一致性 and diversity 多樣性 Unity and diversity among the birds

38 Darwin observed that: Individuals in a population have traits 性狀 that vary Many of these traits are heritable (passed from parents to offspring) More offspring 子代 are produced than survive Competition is inevitable, species generally suit their environment Darwin inferred that: Individuals that are best suited to their environment are more likely to survive and reproduce Over time, more individuals in a population will have the advantageous traits Evolution occurs as the unequal reproductive success of individuals In other words, the environment selects for the propagation of beneficial traits. Darwin called this process natural selection 天擇

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40 Natural selection results in the adaptation of organisms to their environment. Ex. Bat wings are an example of adaptation, Form fits function 型式適合功能 Evolutionary adaptation Natural Selection Evolutionary adaptation 40

41 C. The tree of life 1. Unity in diversity arises from descent with modification. 2.Fossils 化石 provide additional evidence of anatomical unity from descent with modification. 3.Darwin proposed that natural selection could cause an ancestral species to give rise to two or more descendent species 4. Ex. the finch 鶯 species of the Galápagos Islands are descended from a common ancestor 5. Evolutionary relationships are often illustrated with tree-like diagrams that show ancestors and their descendents Descent with modification: adaptive radiation 適應輻射 of finches 雀, 鶯 on the Galápagos Islands 加拉巴哥群島 41

42 1.3: In studying nature, scientists make observations and then form and test hypotheses The word Science is derived from Latin and means to know Inquiry 探究, 探索 is the search for information and explanation The scientific process includes making observations, forming logical hypotheses, and testing them. A. Exploration and observations Biologists describe natural structures and processes This approach is based on observation and the analysis of data 數據. Recorded observations are called data Qualitative data: often take the form of recorded descriptions Quantitative data are generally expressed as numerical measurement, organized into tables and graphs Jane Goodall collecting qualitative data on chimpanzee behavior 42

43 Inductive reasoning 歸納理由 draws conclusions through the logical process of induction Repeating specific observations can lead to important generalizations Ex., the sun always rises in the east or all organisms are made of cells

44 B. Forming and Testing Hypotheses In science a hypothesis 假說 an explanation, based on observations and assumptions, that leads to a testable prediction. It is usually a rational accounting for a set of observations 觀察. It leads to predictions 預測 that can be tested by making additional observations or by performing experiments EX.: i. Observation: Your desk lamp doesn t work ii. Question: Why doesn t your desk lamp work? iii. Hypothesis 1: The bulb is not screwed in properly iv. Hypothesis 2: The bulb is burnt out v. Both these hypotheses are testable A simplified view of the scientific process

45 1. Deductive Reasoning Deductive reasoning 推演 uses general premises to make specific predictions Initial observations may give rise to multiple hypotheses We can never prove that a hypothesis is true, but testing it in many ways with different sorts of data can increase our confidence in it tremendously 2. Questions That Can and Cannot Be Addressed by Science A hypothesis must be testable EX.: a hypothesis that ghosts fooled with the flashlight cannot be tested Supernatural and religious explanations are outside the bounds of science

46 C. The Flexibility of the Scientific Process The scientific method is an idealized process of inquiry However, very few scientific inquiries adhere rigidly to this approach. Backtracking 回溯 and rethinking may be necessary part way through the process le/howscienceworks_01 The process of Science : A more realistic model

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48 D. A Case Study in Scientific Inquiry: Investigating Coat Coloration in Mouse Populations Color patterns of animals vary widely in nature, sometimes even between members of the same species Two populations of mice belonging to the same species (Peromyscus polionotus) but with different color patterns are found in different environments The beach mouse lives on white sand dunes with sparse vegetation; the inland mouse lives on darker soil Different coloration in beach and inland populations of Peromyscus polionotus

49 Inquiry Dose camouflage affect predation on two population of mice? The two types of mice match the coloration of their habitats, natural predators 掠食者 of these mice are all visual hunters Francis Bertody Sumner hypothesized that the color patterns had evolved as adaptations to protect the mice from predators 2010 Hopi Hoekstra and a group of students tested this hypothesis The researchers predicted that mice that did not match their habitat would be preyed on more heavily than mice that did match the surroundings They built models of mice, painted them to match one of the surroundings, and placed equal numbers of each type of model in each habitat They then recorded signs of predation

50 E. Experimental Variables and Controls In a controlled experiment, an experimental group 實驗組 (the non-camouflaged mice in this case) is compared with a control group 對照組 (the camouflaged 偽裝 mice) Experimental variables 變數 are features or quantities that vary in an experiment The independent variable 自變數 is the one that is manipulated by the researchers, while the dependent variable 應變數 is the one predicted to be affected in response F. Theories in Science In the context of science, a theory 理論, 原理, 學說 is broader in scope than a hypothesis, general, and can lead to new testable hypotheses and supported by a large body of evidence in comparison to a hypothesis

51 1.4: Science benefits from a cooperative approach and diverse viewpoints Most scientists work in teams, which often include graduate and undergraduate students Good communication is important in order to share results through seminars 專題討論, publications 出版物, and websites 網路 Science as social process 51

52 A.Building on the work of others Scientists check each others claims by performing similar experiments If experimental results are not repeatable, the original claim will have to be revised It is not unusual for different scientists to work on the same research question Scientists cooperate by sharing data about model organisms 模式生物 (e.g., the fruit fly Drosophila melanogaster) 52

53 B. Science, technology, and society The goal of science is to understand natural phenomena ;the goal of technology is to apply scientific knowledge for some specific purpose Biology is marked by discoveries 發現 while technology is marked by inventions 發明 The combination of science and technology has dramatic effects on society Ethical issues 倫理的爭議 can arise from new technology, but have as much to do with politics, economics, and cultural values as with science and technology DNA technology and crime scene investigation 53

54 C. The Value of Diverse Viewpoints in Science Many important inventions have occurred where different cultures and ideas mix Ex., the printing press 印刷術 relied on innovations from China (paper and ink) and Europe (mass production in mills) Science benefits from diverse views from different racial and ethnic groups, and from both women and men The End