2What is Biology in the 21st 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?
3Course Topics Unit 1 – Introduction Unit 2 - Cells Unit 3 – Genetics Biology 21st centuryChemistry of LifeUnit 2 - CellsStructure and FunctionEnergeticsGrowth and DivisionUnit 3 – GeneticsMeiosisMendelian GeneticsDNA to ProteinsBiotechnologyUnit 4 – EvolutionEvolution by Natural SelectionPopulationsHistory of LifeUnit 5 – ClassificationSystematic TaxonomyPhylogeny and the Tree of LifeBiodiversityUnit 6 - EcologyPrinciples of EcologyInterdependenceBiosphereHuman Impact
4Earth supports an amazing diversity of life biosphere = everywhere life exists
5Earth 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
6Earth supports an amazing diversity of life All levels of life have systems of related partsStructure and function are interdependent in BiologyAll life maintains homeostasis to survive in diverse environmentsEvolution explains the unity and diversity of lifeNothing in Biology makes sense except in the light of evolution.
7Earth 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.
9Earth 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.
10All organisms share certain characteristics. Biology is the scientific study of all forms of life
11Life’s basic characteristic is a high degree of order
12An organism is any individual living thing. All are made of one or more cells.
13What does all life have in common? All are made of one or more cells.All need energy for metabolism.All respond to their environment.All have DNA that they pass on to offspring.
19Energy Flow Activities of life require work SunlightActivities of life require workWork depends on sources of energyEnergy exchange between an organism and environment often involves energy transformationsIn transformations, some energy is lost as heatEnergy flows through an ecosystem, usually entering as light and exiting as heatEcosystemProducers(plants and otherphotosyntheticorganisms)HeatChemicalenergyConsumers(including animals)Heat
21Interaction With Environment and Energy Flow Organisms are open systemsThe dynamics of an ecosystem include two major processesCycling of nutrients, in which materials acquired by plants eventually return to the soilThe flow of energy from sunlight to producers to consumers
24The 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.
26Unifying Themes in Biology All levels of life have systems of related partsStructure and function are interdependent in BiologyAll life maintains homeostasis to survive in diverse environmentsEvolution explains the unity and diversity of lifeNothing in Biology makes sense except in the light of evolution.
27Biological organization is based on a hierarchy of structural levels The biosphereOrganelles1 µmCellEcosystemsCellsAtomsMoleculesCommunities10 µmTissues50 µmPopulationsOrgans and organ systemsOrganisms
28SYSTEMS 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 it’s parts”… a hammer functions because of it’s head and handle- together.Example: Social interactions are affected by the interaction of chemicals in the brain.
32Evolution Evolution is the core theme of biology. Evolution accounts for life’s unity and diversityImplies that all living things are related.The common ancestors are prokaryotes that existed 3.5 billion years ago.
33Evolution unity: all species descended from a common ancestor diversity: modifications that evolved as species branched from their common ancestors
34Unity in the Diversity of Life Underlying life’s diversity is a striking unity, especially at lower levels of organizationIn eukaryotes, unity is evident in details of cell structure15 µm5 µmCilia of ParameciumCilia of windpipe cells
35Can you explain the architecture of eukaryotic cilia?
36The Concept of Natural Selection. DarwinThe Concept of Natural Selection.Observations:a.)Individual variation.b.)Struggle for existence.Inference:a.)Differential reproductive success.b.)Evolutionary adaptationThe 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 evolutionCharles Darwin (1809–1882)
37The Concept of Natural Selection DarwinThe Concept of Natural SelectionThe Origin of Species articulated two main pointsDescent with modification (the view that contemporary species arose from a succession of ancestors)Natural selection (a proposed mechanism for descent with modification)
38AdaptationNatural selection is often evident in adaptations of organisms to their way of life and environmentBat wings are an example of adaptation
39Is 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 life’s unity and diversity to descent with modification.Natural selection eventually produces new species from ancestral species.Thomas Malthus ( )
40Diversification of finches on the Galápagos Islands
41Scientific Inquiry Science “to know” Has limits – only what can be observed and measured.Can’t prove – only disproveMust be able to test (hypotheses)Experimental results must be repeatableUtilizes modeling to represent ideas
42Scientific InquiryInquiry is a search for information and explanation, often focusing on specific questionsThe process of science blends two main processes of scientific inquiry:Hypothesis-based science attempts to seek natural causes and explanations of observationsProposes a possible explanation and tests its validityDiscovery science describes nature through careful observation and data analysisExample of discovery science: understanding cell structure
44Where does it begin?Observation is the active acquisition of information from a primary source. In living beings, observation employs the senses.Your assignmentObserve the object at your tableUse 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 writingPlant, flower, leaf, petal, stem, stalk
45Theory Comprehensive explanation supported by abundant evidence. Newton, Einstein, DarwinGravity, Relativity, Natural SelectionIdea that ties together observations and experimental results that previously seemed unrelated.
46Science, Technology & Society The goal of science is to understand natural phenomenaTechnology applies scientific knowledge for some specific purposeResearch feeds technology and vice versa.
47Data Data are recorded observations Two types Quantitative data: numerical measurementsQualitative data: recorded descriptionsInductive reasoning involves generalizing based on many specific observation
49Paul Serrano is digging into the past Behavioralist Jane Goodall recording observations on chimpanzeesDavid Reznick conducting field experiments on guppy evolution in TrinidadPaul Serrano is digging into the past
50Energy Interdependence Structure to function Science, Technology & SocietyEnergyInterdependence
51Dilemma: 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.
52Dilemma: How to study Biology? Systems Biologyseeks to understand the behavior of a whole system rather than its partsSeeks to create models of the dynamic behavior of whole biological systemsAn 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.
53Systems biology uses three key research developments: High-throughput technology: methods to generate large data sets rapidlyBioinformatics: using computers and software to process and integrate large data setsInterdisciplinary research teams