Unformatted text preview: BIO115
Introduction to Biology Dr. Jessica Pamment Lectures Monday 9:40 – 11:10 Byrne Hall Room 352 Wednesday 9:40 – 11:10 Byrne Hall Room 352 COURSE REQUIREMENTS Punctual class attendance & sign in sheet One midterm exam and one final exam 2 quizzes 5 homework assignments GRADING
A. Midterm 1 (20%) B. Final exam (25%) C. Quizzes (20%) D. Homework assignments (35%) Textbook:
Essential Biology, Fourth Edition
Campbell, Reece & Simon Pearson Benjamin Cummings Essential Biology 4th Edition
Core areas: 1. Cells 2. Genetics 3. Evolution 4. Ecology Main goals: 1. Relate content of course to every day lives 2. Clarify process of science 3. Emphasize evolution as the core unifying theme in biology Student Learning Objectives
To understand the basic principles of Biological Sciences 1. Chemical foundation of biological sciences 1. Basics of composition of prokaryotic and eukaryotic cells 1. Principles of cell energy conversion, respiration, and photosynthesis 4. Basic understanding of DNA replication and cell division 5. Principles of gene expression, from transcription to protein synthesis 6. Biotechnology: relevance to our everyday lives Biology is everywhere! everywhere! Overview
• What is biology and why is it important? • The characteristics and organization of life • Evolution, the main unifying theme of biology • Scientific Method What is Biology?
• Greek origin • Bio life • Logos thought • Studies living organisms and their environment Properties of Life
Order Response to the environment Evolutionary adaptation Regulation Energy processing Reproduction Growth and development Levels of Biological Organization Levels
1. The biosphere 6. Organs and organ systems 2. Ecosystems 9. Organelles 3. Communities Atoms
50 µm 8. Cells 7. Tissues 4. Populations 5. Organisms 10. Molecules Levels of Biological Organization Organization Levels of Biological Organization Organization Levels of Biological Organization Organization Ecosystems Ecosystems
• Living and nonliving components of a particular area • Organisms interact continuously with their environment • Nutrients get recycled • Energy changes form Ecosystems Ecosystems
• Dynamics of any ecosystem depends on: • The cycling of nutrients • The flow of energy Energy and Nutrient Flow in an Ecosystem Ecosystem Cells Cells
• A cell is the lowest level of structure that can perform all activities required for life Cells Cells
• Are the basic unit of living organisms • Are either prokaryotic or eukaryotic • Use DNA as chemical material of genes Eukaryotic Eukaryotic and Prokaryotic Cells The The Language of DNA DNA Technology in the Drug Industry DNA Technology in the Drug Industry The Diversity of Life The Diversity of Life • More than 1 million insects • Over 290,000 plants • Almost 52,000 vertebrates The Three Domains of Life The Three Domains of Life
1. Domain Bacteria prokaryote 1. Domain Archaea prokaryote 1. Domain Eukarya eukaryote i. Kingdom Plantae ii. Kingdom Fungi iii. Kingdom Animalia iv. Kingdom Protists The Three Domains of Life The Three Domains of Life EUKARYA
Land plants Green algae Dinoflagellates Forams Diatoms Ciliates Red algae Cellular slime molds Animals Amoebas Euglena Trypanosomes Leishmania Fungi Sulfolobus Thermophiles Green nonsulfur bacteria (Mitochondrion) Spirochetes Chlamydia Green sulfur bacteria Halophiles COMMON ANCESTOR OF ALL LIFE Methanobacterium BACTERIA
Cyanobacteria (Plastids, including chloroplasts) ARCHAEA Summary
• Biology is the study of life • Cells are an organism’s basic unit of structure and function • Organisms interact with their environment exchanging matter and energy Summary
The continuity of life is based on heritable information in the form of DNA • Evolution accounts for the unity and diversity of life Evolution Overview
• History timeline • Charles Darwin’s theory of evolution • Evidence for evolution Biology’s Unifying Theme
EVOLUTION Explains unity of all living things despite physical differences The central organizing concept in biology is that all of life has a common origin and has changed and developed through the process of evolution Evolution
• Evolution is biology’s core theme • Process by which inherited traits in a population of organisms change from one generation to the next species • Species living today descended from ancestral History of Evolution
• 384322 B.C. Aristotle viewed species as fixed • C18th Erasmus Darwin suggested all species arose from evolution no mechanism • 1809 JeanBaptiste Lamarck suggested ‘inheritance by acquired characteristics’ History of Evolution • 18091882 Charles Darwin proposed a theory of evolution through natural selection • Alfred Russell Wallace sends a manuscript to Darwin proposing same theory The Origin of Species
• Darwin’s take home messages from his book: 1. Species alive today descended from ancestral species by the process of evolution 2. Natural selection is the mechanism for this process Evidence for Evolution
• Direct observation • The fossil record • Homologies Artificial Selection Terminal bud Lateral buds Brussels sprouts Cabbage Flower clusters Leaves Kale Stem Wild mustard Flowers and stems Broccoli Kohlrabi Cauliflower Artificial Selection Artificial Selection Fossil Fossil Evidence (a) Pakicetus (terrestrial) (b) Rhodocetus (predominantly aquatic) Pelvis and hind limb (c) Dorudon (fully aquatic) (d) Balaena (recent whale ancestor) Pelvis and hind limb Homologous Structures
umerus adius lna arpals etacarpals halanges Human Cat Whale Bat Natural Selection Natural Selection
• Process by which heritable traits become more common in a population over successive generations • These heritable traits make it more likely for an organism to survive and successfully reproduce Beak Variation in Galapagos finches (a) Cactus-eater (c) Seed-eater (b) Insect-eater Warbler finches Insect-eaters Green warbler finch COMMON ANCESTOR Gray warbler finch Seed-eater Sharp-beaked ground finch Bud-eater Vegetarian finch Mangrove finch Insect-eaters Cactus-flowereaters Seed-eaters Tree finches Ground finches Woodpecker finch Medium tree finch Large tree finch Small tree finch Large cactus ground finch Cactus ground finch Small ground finch Medium ground finch Large ground finch Descent with modification Darwin’s Observations
• Darwin based his mechanism of natural selection on: competition • Observation 1: Overproduction and • Observation 2: Individual variation • Conclusion: Unequal reproductive success Natural Selection 1 Varied inherited traits. 2 Elimination of certain traits 3 Reproduction of survivors. 4 Increasing frequency of beneficial traits. Natural Selection in Action Natural Selection in Action
• Antibiotic resistant bacteria • Drug resistant HIV Summary
• Evolution accounts for the unity and diversity of life • Darwin suggested natural selection as a mechanism of evolution • Natural selection is ongoing today What is Science? What is Science?
• Science: from latin ‘to know’ • 1. 2.
Two main scientific approaches: Discovery science Hypothesisdriven science Discovery Science Discovery Science
• Consists of verifiable observations and measurements • Leads to conclusions based on inductive reasoning • From specific observations to generalization Discovery Discovery Science HypothesisDriven Science HypothesisDriven Science
• The most popular way of following the scientific method • Consists of series of steps starting with a hypothesis that is formed • Uses deductive reasoning question leads to specific answer The The Scientific Method The The Scientific Method The The Scientific Method Scientific Method Observations Question Hypothesis #1: Dead batteries Hypothesis #2: Burnt-out bulb Scientific Method Hypothesis #1: Dead batteries Hypothesis #2: Burnt-out bulb Prediction: Replacing batteries will fix problem Prediction: Replacing bulb will fix problem Test prediction Test prediction Test falsifies hypothesis Test does not falsify hypothesis Hypothesis vs. Theory Hypothesis vs. Theory
• A theory is a hypothesis that has been repeatedly tested with little modification • A theory is much broader in scope than a hypothesis • A hypothesis is considered valid until it can be falsified Science Science
• Good science is not dogmatic; it is an ongoing process of testing and evaluation • Science is just one way of knowing about our world • Art and religion are other ways Case Study: Can colors protect a Case Study: Can colors protect a snake? Mimicry in Snakes Mimicry
Observation: Question: What is the function of such mimicry? Case Study: Can colors protect a Case Study: Can colors protect a snake?
• Hypothesis: the king snake’s resemblance to the coral snake repels predators • Prediction: predators will attack brightly colored snakes less often than snakes lacking bright coloration Case Study: Can colors protect a Case Study: Can colors protect a snake?
• Experiment: Use artificial snakes with either plain brown or bright coloration • Equal numbers placed in fields • Recorded number of attacks Artificial Snakes Snakes Results Results Key Features of Scientific Inquiry Key Features of Scientific Inquiry
• A dependence on observations and measurements that can be verified by others • Hypotheses must be testable by experiments others can repeat Summary Summary
• Discovery science observations that can be verified by others • Hypothesisdriven coming up with testable hypothesis to answer questions about observations • Importance of developing scientific and technological literacy in today’s society ...
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- Winter '11
- Biology, Darwin's finches, Birds of Ecuador, The Scientific Method