Labs Start Next Week Lab Manual available in bookstore buy it before class.

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1 Biology 178 Biology, Fall 2008 Instructor: Dr. Kurt Toenjes, Phone: Room: 133 Science Hall Textbook: BIOLOGY, 8 th Edition by Raven et al. Course Introduction and Objectives: Assessment: Grading: Academic Honesty: Attendance: Schedule: Course Introduction Labs Start Next Week Lab Manual available in bookstore buy it before class. Required Texts: Biology Raven et al. (8 th Ed.) Laboratory manual Vodopich and Moore (8 th Ed.) Grading: REFER TO SYLLABUS save this in an organized location, it is your reference guide.

2 How to succeed in Biology 178: 1) Study every single day, including weekends 2) Stay organized 3) Plan ahead for exams 4) Come to class Course Introduction Take notes, ask questions Use the text as a supplement to the lectures Review lectures on the course website 5) Come see me with questions before the test 6) Make sure I know your name Chapter 1 The Science of Biology LECTURE OUTLINE I. Properties of Life II. Hierarchical Organization of Life III. The Nature of Science IV. Stages of a Scientific Investigation V. What is Scientific Theory VI. Unifying Themes in Biology A replica of the Beagle.

3 What is Biology? Study of life Search for order in the natural world Discovery of new relationships Learning the working rules that allow life to exist The Importance of Biology

4 I. Properties of Life Basic characteristics of living organisms a. cellular organization b. order c. sensitivity d. growth, development, and reproduction e. energy utilization f. evolutionary adaptation g. homeostasis Oil and Water: Alive or not alive? Alive or not alive? I. Properties of Life Basic characteristics of living organisms a. cellular organization b. order c. sensitivity d. growth, development, and reproduction e. energy utilization f. evolutionary adaptation g. homeostasis Oil and Water: Alive or not alive? Alive or not alive?

5 II. Hierarchical Organization of Life Life s levels of organization define the scope of biology II. Hierarchical Organization of Life Emergent properties New properties arise at each higher level Paramecium

6 III. The Nature of Science 1. Hypothesis Testing Hypothesis (= assumption in ancient Greek) is a proposed explanation for a phenomenon (an educated guess) III. The Nature of Science 2. Reasoning a. Deductive Reasoning (Predictions) Apply general principles to predict specific results e.g. If organisms are composed of cells & humans are organisms, then humans are composed of cells b. Inductive Reasoning Use specific observations to construct general principles e.g. If animals are composed of cells & plants are composed of cells, & fungi are composed of cells, than perhaps all living things are composed of cells

7 IV. Stages of a Scientific Investigation Observation Question All science begins with an observation. Hypothesis(es) A hypothesis is a suggested explanation that accounts for an observation. Prediction(s) Controlled Experiment An experiment is used to test a hypothesis, and/or eliminate one or more multiple hypotheses Conclusion IV. Stages of a Scientific Investigation

8 IV. Stages of a Scientific Investigation Steps in the scientific method: (1) Observation Francesco Redi in 1600 s Maggots appear on fresh meat left uncovered. Flies swarm over raw meat (2) Hypothesis A tentative testable explanation of an observed event. Maggots appear on fresh meat left uncovered because flies land on the meat and lay eggs. IV. Stages of a Scientific Investigation Steps in the scientific method... (3) Experiment a study to test a hypothesis Simple experiments Test single variable AT A TIME Experimental Variable AKA the Treatment Control all other variables Hold them constant in controls Maggots No maggots What were his results?

9 IV. Stages of a Scientific Investigation Steps in the scientific method... (4) Conclusion In this case, the hypothesis is supported by the results of the experiment Maggots No maggots IV. Stages of a Scientific Investigation O"Q " H " P " Controlled Experiments " Conclusions Manuscript preparation for publication Peer Review Publication Replication by other scientists Acceptance by the scientific community

10 IV. Stages of a Scientific Investigation Science is a human endeavor. Real scientific advances often involve: accidents and insight lucky guesses controversies between scientists i.e. Discovery of penicillin by Alexander Fleming, 1928 Penicillin prevents the growth of staphylococci bacteria, an organism causing serious infection at that time Theory: Scientific versus general

11 Theory: Scientific versus general In one episode of 'Cheers', Cliff is seated at the bar describing the Buffalo Theory to Norm. "Well you see, Norm, it's like this... A herd of buffalo can only move as fast as the slowest buffalo. And when the herd is hunted, it's the slowest and weakest ones at the back that are killed first. This natural selection is good for the herd as a whole, because the general speed and health of the whole group keeps improving by the regular killing of the weakest members. 1. A set of statements or principles devised to explain a group of facts or phenomena, especially one that has been repeatedly tested or is widely accepted and can be used to make predictions about natural phenomena. Theory: Scientific versus general In one episode of 'Cheers', Cliff is seated at the bar describing the Buffalo Theory to Norm. "Well you see, Norm, it's like this... A herd of buffalo can only move as fast as the slowest buffalo. And when the herd is hunted, it's the slowest and weakest ones at the back that are killed first. This natural selection is good for the herd as a whole, because the general speed and health of the whole group keeps improving by the regular killing of the weakest members. In much the same way, the human brain can only operate as fast as the slowest brain cells. Now, as we know, excessive intake of alcohol kills brain cells. But naturally, it attacks the slowest and weakest brain cells first. In this way, regular consumption of beer eliminates the weaker brain cells, making the brain a faster and more efficient machine. And that, Norm, is why you always feel smarter after a few beers..." 1. A set of statements or principles devised to explain a group of facts or phenomena, especially one that has been repeatedly tested or is widely accepted and can be used to make predictions about natural phenomena. 2. An assumption based on limited information or knowledge; a conjecture.e; a conjecture.

12 V. What is a Scientific Theory? A theory is: a hypothesis supported by a wealth of scientific evidence interconnected concepts, supported by experimental evidence solid ground of science capable of predicting future occurrences or observations of the same kind V. What is a Scientific Theory? Examples of Theories in Science: 1. Cell Theory 2. Theory of Relativity 3. Theory of Evolution

13 Theory: Scientific versus general Cell theory Theory: Scientific versus general Stem Cell theory

14 Theory: Scientific versus general Stem Cell use in wound repair Theory: Scientific versus general Stem Cell use in wound repair

15 Theory: Scientific versus general Stem Cell use in wound repair Debate is an important part of science

16 Not a current scientific debate Natural selection and evolution versus Creative Design Not a current scientific debate Natural selection and evolution versus Creative Design

17 V. What is a Scientific Theory? Example of the Development of a Theory: Evolution Accepted Belief in 1831: Species have been specifically created and are unchangeable over time. Darwin s Evidence to the Contrary: Fossil record Geographical Variability Island Modifications V. What is a Scientific Theory? The Basics of the Theory of Evolution Darwin & Wallace 1800 s (1) Genetic variation: exists among members of a population (2) Inheritance of variations: parents to offspring (3) Natural selection: Enhanced survival/reproduction of organisms with adaptations to survive Present-day organisms descended, with modification, from pre-existing forms or Change over time

18 V. What is a Scientific Theory? Further Evidence Supporting the Theory of Evolution: 1. The Fossil Record 2. The Age of the Earth 3. The Mechanisms of Heredity 4. Comparative Anatomy 5. Molecular and Phylogenetic Evidence (DNA) Figure 1.13 V. What is a Scientific Theory? What is Biology? Unifying Themes of Biology 1. Cell theory 2. Molecular basis of inheritance 3. Evolution

19 VI. Unifying Themes in Biology What is Biology? 1. Cell Theory Robert Hooke (1665): Discovered cells Schleiden and Schwann (1839): All living things are composed of cells Modern Cell Theory: All living organisms are made of cells, and all living cells come from other living cells. 2. Molecular basis of inheritance DNA encodes genes which make-up and control living organisms. Heredity is dependent on the faithful copying of the cell s DNA into daughter cells. 3. Evolution conservation Some fundamentally important characteristics of earlier organisms are preserved and passed on to future generations. e.g. Histones (chief proteins of chromatin) adaptation Life-forms have evolved varying characteristics to adapt to varied environments. This has resulted in incredible diversity.