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Biology The Study of Life Slide 2 What is Biology in the 21 st Century? How is studying Biology different today than in the past? How does studying Biology affect your life? Why should you take this class? How has advancement in science benefited humanity? Slide 3 Course Topics Unit 1 Introduction Biology 21 st century Chemistry of Life Unit 2 - Cells Structure and Function Energetics Growth and Division Unit 3 Genetics Meiosis Mendelian Genetics DNA to Proteins Biotechnology Unit 4 Evolution Evolution by Natural Selection Populations History of Life Unit 5 Classification Systematic Taxonomy Phylogeny and the Tree of Life Biodiversity Unit 6 - Ecology Principles of Ecology Interdependence Biosphere Human Impact Slide 4 Earth supports an amazing diversity of life biosphere = everywhere life exists Slide 5 Earth supports an amazing diversity of life Every part of the biosphere is connected with every other part. The biosphere includes many environments. Biodiversity increases at the equator and decreases toward the poles Slide 6 Earth supports an amazing diversity of life 1.All levels of life have systems of related parts 2.Structure and function are interdependent in Biology 3.All life maintains homeostasis to survive in diverse environments 4.Evolution explains the unity and diversity of life Nothing in Biology makes sense except in the light of evolution. Slide 7 Earth supports an amazing diversity of life A biological species is defined as a group of individuals that will breed to reproduce. Scientists have described over 1.7 million of the world's species of animals, plants and algae, as of 2010. Mammals make up one of the smallest groups, with just 5,490 members. Altogether the earth's oceans, lakes, continents and islands support over 62,000 identified species of vertebrate animals and 320,000 species of plants. Slide 8 A small sample of biological diversity Slide 9 Earth supports an amazing diversity of life So...how many are there? According to a new report co- authored by Derek Tittensor at UNEP's World Conservation Monitoring Centre (UNEP- WCMC), in Cambridge, UK, the estimate is around 8.7 million. 86% of all species on land and 91% of those in the seas have yet to be discovered, described or catalogued. Slide 10 All organisms share certain characteristics. Biology is the scientific study of all forms of life Slide 11 Lifes basic characteristic is a high degree of order Slide 12 An organism is any individual living thing. All are made of one or more cells. Slide 13 All need energy for metabolism. What does all life have in common? All are made of one or more cells. All respond to their environment. All have DNA that they pass on to offspring. Slide 14 Properties of Life Slide 15 cellular structure Slide 16 Microscope Hooke (1665) English, observed cork- dead plant material, 30x, cells Leeuwenhoek (Dutch), observed pond water, 300x, 1st living cells animacules, protists, sperm, blood Slide 17 Cell Theory Schleiden Schwann Virchow a)All living things consist of cells. b)Cells are an organisms basic unit of structure and function. c)All cells come from other cells. Slide 18 Metabolism Energy Utilization Slide 19 Energy Flow Activities of life require work Work depends on sources of energy Energy exchange between an organism and environment often involves energy transformations In transformations, some energy is lost as heat Energy flows through an ecosystem, usually entering as light and exiting as heat Sunlight Ecosystem Heat Chemical energy Consumers (including animals ) Producers (plants and other photosynthetic organisms) Slide 20 Respond to their environment Slide 21 Interaction With Environment and Energy Flow Organisms are open systems The dynamics of an ecosystem include two major processes Cycling of nutrients, in which materials acquired by plants eventually return to the soil The flow of energy from sunlight to producers to consumers Slide 22 reproduction Slide 23 Heredity Slide 24 The genetic material: DNA DNA (deoxyribonucleic acid) The substance of genes- instructions to make protein and protein makes the organism what it is. Units of inheritance passed from parents to offspring. Double stranded molecule made of 4 nucleotides (ATGC). Human genome is 6 billion nucleotides long in 23 pairs of chromosomes. Slide 25 Growth and Development Slide 26 Unifying Themes in Biology 1.All levels of life have systems of related parts 2.Structure and function are interdependent in Biology 3.All life maintains homeostasis to survive in diverse environments 4.Evolution explains the unity and diversity of life Nothing in Biology makes sense except in the light of evolution. Slide 27 Biological organization is based on a hierarchy of structural levels Ecosystems The biosphere Organisms Populations Communities Cells Organelles Molecules Tissues Organs and organ systems Cell 1 m Atoms 10 m 50 m Slide 28 SYSTEMS and Emerging Properties Each level, ATOM to the BIOSPHERE, is organized. Unique properties are revealed at each level- they emerge Properties result from interactions between the components. The total is greater than the sum of its parts a hammer functions because of its head and handle- together. Example: Social interactions are affected by the interaction of chemicals in the brain. Slide 29 Form fits function Slide 30 Homeostasis Slide 31 Evolutionary Adaptation Slide 32 Evolution Evolution is the core theme of biology. Evolution accounts for lifes unity and diversity Implies that all living things are related. The common ancestors are prokaryotes that existed 3.5 billion years ago. Slide 33 Evolution unity: all species descended from a common ancestor diversity: modifications that evolved as species branched from their common ancestors Slide 34 Unity in the Diversity of Life Underlying lifes diversity is a striking unity, especially at lower levels of organization In eukaryotes, unity is evident in details of cell structure Cilia of windpipe cells Cilia of Paramecium 15 m5 m Slide 35 Can you explain the architecture of eukaryotic cilia? Slide 36 Observations: a.)Individual variation. b.)Struggle for existence. Inference: a.)Differential reproductive success. b.)Evolutionary adaptation The evolutionary view of life came into sharp focus in 1859, when Charles Darwin published On the Origin of Species by Natural Selection Darwinism became almost synonymous with the concept of evolution Darwin The Concept of Natural Selection. Charles Darwin (18091882) Slide 37 The Origin of Species articulated two main points The Origin of Species articulated two main points Descent with modification (the view that contemporary species arose from a succession of ancestors) Descent with modification (the view that contemporary species arose from a succession of ancestors) Natural selection (a proposed mechanism for descent with modification) Natural selection (a proposed mechanism for descent with modification) Darwin The Concept of Natural Selection Slide 38 Adaptation Natural selection is often evident in adaptations of organisms to their way of life and environment Bat wings are an example of adaptation Slide 39 Is evolutionary adaptation a product of natural selection? Thomas Malthus: organisms will produce more offspring than can be supported with available resources. Survival of the fittest- fitness is measured by reproductive success. Many related organisms have similar features adapted for specific ways of life. Such kinships connect lifes unity and diversity to descent with modification. Natural selection eventually produces new species from ancestral species. Natural selection eventually produces new species from ancestral species. Thomas Malthus (1766-1834) Slide 40 Diversification of finches on the Galpagos Islands Slide 41 Scientific Inquiry Science to know Has limits only what can be observed and measured. Cant prove only disprove Must be able to test (hypotheses) Experimental results must be repeatable Utilizes modeling to represent ideas Slide 42 Scientific Inquiry Inquiry is a search for information and explanation, often focusing on specific questions The process of science blends two main processes of scientific inquiry: Hypothesis-based science attempts to seek natural causes and explanations of observations Proposes a possible explanation and tests its validity Discovery science describes nature through careful observation and data analysis Example of discovery science: understanding cell structure Slide 43 Idealized version of Scientific Process Slide 44 Where does it begin? Observation is the active acquisition of information from a primary source. In living beings, observation employs the senses. Your assignment Observe the object at your table Use your senses to describe the object. In your notebook, write a minimum of one page describing the object in front of you. You may not use the following terms in your writing Plant, flower, leaf, petal, stem, stalk Slide 45 Theory Comprehensive explanation supported by abundant evidence. Newton, Einstein, Darwin Gravity, Relativity, Natural Selection Idea that ties together observations and experimental results that previously seemed unrelated. Slide 46 Science, Technology & Society The goal of science is to understand natural phenomena Technology applies scientific knowledge for some specific purpose Research feeds technology and vice versa. Slide 47 Data Data are recorded observations Two types Quantitative data: numerical measurements Qualitative data: recorded descriptions Inductive reasoning involves generalizing based on many specific observation Slide 48 Science is a social process Slide 49 David Reznick conducting field experiments on guppy evolution in Trinidad Paul Serrano is digging into the past Behavioralist Jane Goodall recording observations on chimpanzees Slide 50 Science, Technology & Society Energy Structure to function Interdependence Slide 51 Dilemma: How to study Biology? something complex such as an organism or cell cannot be analyzed without taking it apart. If you take something apart it disrupts the system and interferes with the meaningful understanding of how it works. Slide 52 Dilemma: How to study Biology? Systems Biology seeks to understand the behavior of a whole system rather than its parts Seeks to create models of the dynamic behavior of whole biological systems An example is a systems map of how proteins interact in a fruit fly cell. The model may predict how a change in one part of a system will affect the rest of the system. Slide 53 Systems biology uses three key research developments: High-throughput technology: methods to generate large data sets rapidly Bioinformatics: using computers and software to process and integrate large data sets Interdisciplinary research teams Slide 54