UNIT I – UNITY & DIVERSITY OF LIFE

1. UNIT I – UNITY & DIVERSITY OF LIFE Hillis ~ Ch 1, 19, 20, 22 Big Campbell ~ Ch 1, 19, 27, 28, 31 Baby Campbell ~ Ch 1, 10, 16, 17

2. Biology is . . .

3. I. “THE STUDY OF . . . “ – EXPERIMENTAL DESIGN Inquiry-based

4. I. EXPERIMENTAL DESIGN, cont • Types of Experiments • Comparative • Observational • Controlled • Setting up a Controlled Experiment • Valid, clear hypothesis • Testable statement or prediction • Do not use “I think …”, “My hypothesis is …”, etc! • Often written in “If …, then …” format but not a requirement • Control Group • Benchmark or standard for comparison • Experimental or Test Group(s) • Only one factor can be changed in each test • Independent (Manipulated) Variable • Dependent (Responding) Variable

5. I. EXPERIMENTAL DESIGN, cont • Setting up a Controlled Experiment, cont • Controlled variables (aka control variables, constants) must be monitored • Additional factors that could change from one set-up to another • Sample Size • Minimize potential sources of error • Importance of Repeatable Results • Presentation of Data • Concise & Organized • Tables • Graphs • Descriptive title • Key • Units must be evenly spaced (line break) and labeled • Use at least half of available space

6. I. EXPERIMENTAL DESIGN, cont • Graphs, cont • DRY MIX • Continuous Independent Variable (time) → ____________ Graph • Discrete Independent Variable → _________________ Graph • Part of a Whole → _________________ Graph

7. I. EXPERIMENTAL DESIGN, cont • Graphs, cont • For Height Lab … • Mean • Median • Mode • Range • Histogram • Normal Distribution?

8. I. EXPERIMENTAL DESIGN, cont • Normal Distribution • Bell Curve • Standard Deviation

9. I. EXPERIMENTAL DESIGN, cont • Data Analysis • Null Hypothesis • “Statement of No Effect” • For example, • There are no significant differences between predicted and observed data. • There are no significant differences between control group data and test group data.

10. I. EXPERIMENTAL DESIGN, cont • Statistical Analysis – Supports or refutes null hypothesis • T Test • Allows for comparison of the means between 2 data sets • In other words, is there a significance difference in the means or can they be considered the same? • Most often used to analyze continuous data • Chi Square Analysis • Measures variation of observed test results from expected results to determine if differences are significant • Most often used for categorical data

11. I. EXPERIMENTAL DESIGN, contChi Square Analysis • Use the Chi Square formula to find the sum of the variation in the data. This value is Chi Square. • The Chi Square value is then compared to the critical value in the Probability Table for 0.05 with the correct degrees of freedom. By convention, this is the accepted probability value in science. • Degrees of freedom = n – 1 where n represents # categories, possible outcomes

12. I. EXPERIMENTAL DESIGN, contChi Square Analysis • If the Chi Square value is less than the value listed under 0.05, the null hypothesis is accepted. • Interpretation → The probability that the differences are due to chance is greater than 0.05; therefore the differences between the data are considered random and statistically insignificant. • If the Chi Square value is equal to or greater than the value listed, the null hypothesis is rejected. • Interpretation → The probability that the differences are due to chance is less than or equal to 0.05; therefore the differences between the data are statistically significant and cannot be considered due to random error.

13. I. EXPERIMENTAL DESIGN, cont • A poker-dealing machine is supposed to deal cards at random, as if from an infinite deck. In a test, you counted 1600 cards and observed the following: • Spades = 404 • Hearts = 420 • Diamonds = 400 • Clubs = 376 • Is the machine dealing randomly? • Null Hypothesis: • Chi Square Formula: • Expected =

14. I. EXPERIMENTAL DESIGN, cont

15. I. EXPERIMENTAL DESIGN, cont • Chi Square = • Degrees of Freedom = • P Value • Interpretation:

16. I. EXPERIMENTAL DESIGN, cont • Conclusion • Evaluate hypothesis • Was it supported, refuted, or were results inconclusive? • Assess experimental design • Was there only one independent variable? • Were sources of error minimized? • Controlled variables/constants • Repeatable? • Theory

17. II. UNITY OF LIFE • Form vs. Function • Characteristics of Life • All living things are made of ____________.

18. II. UNITY OF LIFE, cont. • Characteristics of Life, cont

19. III. HIERARCHY OF LIFE • Organization of Life

20. III. HIERARCHY OF LIFE, cont • Classification of Life

21. III. HIERARCHY OF LIFE, cont • A Closer Look at Classification • Domain ________________ • Kingdom ________________________ • Domain ________________ • Kingdom ________________________ • Domain ___________________ • Kingdom ________________________ • Kingdom ________________________ • Kingdom ________________________ • Kingdom ________________________

22. IV. CHALLENGING THE BOUNDARIES OF LIFE • Viruses . . . Living or Non-living? • Discovery of Viruses • First isolated by Ivanowsky in 1890s from infected tobacco leaves • Crystallized by Stanley in 1935 – proved viruses were not cells • Not capable of carrying out life processes without a host cell • Parasites

23. IV. BOUNDARIES, cont • Viruses, cont • Structures found in all viruses: • Viral genome • DNA or RNA. • May be single-stranded or double-stranded • Protein coat • Known as a capsid • Made up of protein subunits called capsomeres. • Structures/adaptations that may be present: • Viral envelope • Typically derived from host cell membrane • Exception is Herpes virus, synthesized from nuclear envelope of host cell • Aid in attachment. Envelope glycoproteins bind to receptor molecules on host cell • Most viruses that infect animals have envelope • Tail – Found in some viruses to aid in attachment

24. IV. BOUNDARIES, cont

25. IV. BOUNDARIES, cont • Viruses, cont. • Bacteriophage • Infect bacteria • Bacterial Defense Mechanisms • Restriction Enzymes • Coexistence

26. IV. BOUNDARIES, cont – Viral Replication

27. IV. BOUNDARIES, cont – Viral Replication Viral Entrance into Host Cell

28. IV. BOUNDARIES, cont – Viral Replication LYTIC CYCLE 1. Lytic Cycle – Results in death of host cell.

29. IV. BOUNDARIES, cont – Viral Replication LYSOGENIC CYCLE

30. IV. BOUNDARIES, cont – Human Viruses • DNA Viruses • No envelope • Papilloma Virus • With envelope • Smallpox Virus • Herpesvirus • Herpes simplex I and II • Epstein-Barr virus • Varicella zoster

31. IV. BOUNDARIES, cont – Human Viruses • RNA Viruses • No envelope • Rhinovirus • Envelope • Coronavirus • Influenza virus • Filovirus • HIV • Belongs to a group of viruses known as _____________________ • Contain RNA, reverse transcriptase • Converts ________ to __________

32. IV. BOUNDARIES, cont – HIV • Human Immunodeficiency Virus • Infects WBCs known as Helper T cells • Can reside in lysogenic-like cycle for years • Active, symptomatic = AIDS

33. IV. BOUNDARIES, cont • Viroids • Single, circular RNA molecule; lack protein • Parasitize plants • Prions • Infectious proteins; lack nucleic acid • Cause Mad Cow Disease, Creutzfeldt-Jakob Disease • Very long incubation period • No treatment

34. V. THE DIVERSITY OF LIFE

35. VI. PROKARYOTES – A CLOSER LOOK

36. VI. PROKARYOTES, cont • Archaebacteria • Examples include methanogens, thermoacidophiles, halophiles • TaqDNA polymerase

37. VI. PROKARYOTES, cont Eubacteria • Ubiquitous • May be pathogenic • Most are _________________ • Classification • Shape • Cocci • Bacilli • Spirilla • Gram Stain Reaction • Positive • Negative

38. VI. PROKARYOTES – EUBACTERIA, cont • Nucleoid region • Plasmids • Asexual reproduction • Binary fission

39. VI. PROKARYOTES – EUBACTERIA, cont • Adaptations • Capsule • Adherence • Protection • Associated with virulence • Pili • Adherence • Conjugation • Endospore • Bacterial hibernation” • Motility

40. VI. PROKARYOTES – EUBACTERIA, cont Adaptations, cont Quorum Sensing/Biofilms Fairly recent discovery Bacteria exchange chemical communication signals Multicellularity??? “Sexual Reproduction” Transformation Transduction Conjugation

41. VI. PROKARYOTES – EUBACTERIA, cont • Metabolism • Nitrogen fixation • Conversion of atmospheric nitrogen (N2) to ammonium (NH4+) • Metabolic Cooperation • Biofilms • Oxygen relationships • Obligate aerobes • Facultative anaerobes • Obligate anaerobes

42. VI. PROKARYOTES – EUBACTERIA, cont • Bacterial Pathogenesis • “Normal Flora” • Some bacteria are opportunistic pathogens • Toxin Production • Exotoxins • Bacterial proteins that can produce disease w/o the prokaryote present • Examples include botulism, cholera • Endotoxins • Components of gram negative membranes • Examples include typhoid fever, Salmonella food poisoning

43. VI. PROKARYOTES – EUBACTERIA, cont • Bacterial Pathogenesis, cont • Examples • Clostridium sp. • Staphylococcus • Streptococcus • Neisseria sp. • Mycobacterium tuberculosis

44. EUKARYOTES

45. VII. KINGDOM PROTISTA • Very diverse • All __________________ • Mostly _________________ • Classified according to eukaryotic kingdom protist is most like, nutrition • Animal-like • Ingestive • Protozoans • Plant-like • Photosynthetic • Algae • Fungus-like • Absorptive • Slime Molds

46. VII. KINGDOM PROTISTA, cont Protist Phylogeny . . . For now!

47. VII. KINGDOM PROTISTA, cont • Important Protozoans • Zooplankton • Important component of aquatic food chains • Euglena • Protozoan or Algae?? • Autotrophic/heterotrophic • Pellicle • Entamoeba • Intestinal pathogen • Associated with dirty, stagnant water • Moves, feeds using pseudopods • Giardia • Lack mitochondria, cell walls • Live in fresh water; flagellated • Intestinal pathogens

48. VII. KINGDOM PROTISTA, cont • Important Protozoans, cont • Trypanosoma • Tse-tse fly vector • Blood pathogen; flagellated • Causes sleeping sickness • Plasmodium • Belong to Apicomplexa • All parasitic, non-motile • Cause malaria • Vector = Anopheles mosquito • Resistance seen in _________ ________________________

49. VII. KINGDOM PROTISTA, cont • Algae • Very important aquatic producers • Phytoplankton • Include • Dinoflagellates • Red Tides • Diatoms • Make up most of Earth’s phytoplankton • Have glass-like silicon shells • Brown Algae • Kelp • Rhodophyta • ______ Algae • Seaweed • Also found in coral reefs • Chlorophyta • ________ Algae

50. VIII. KINGDOM FUNGI