UNIT I UNITY DIVERSITY OF LIFE Big Campbell
UNIT I – UNITY & DIVERSITY OF LIFE Big Campbell ~ Ch 1, 19, 27, 28, 31 Baby Campbell ~ Ch 1, 10, 16, 17
Biology is. . .
I. “THE STUDY OF. . . “ – EXPERIMENTAL DESIGN • Inquiry-Based • The Scientific Process o Organized means to solve problems, answer questions o Five general steps 1) 2) 3) § § Generally based on both observations & inductive reasoning Inductive reasoning v Specific → General § Deductive reasoning v General → Specific 4) 5)
I. EXPERIMENTAL DESIGN, cont • Types of Experiments o Comparative o Observational o Controlled • Setting up a Controlled Experiment o Valid, clear hypothesis Ø Testable statement or prediction Ø Do not use “I think …”, “My hypothesis is …”, etc! Ø May be written in “If …, then …” format but not required o Control Group Ø Benchmark or standard for comparison o Experimental or Test Group(s) Ø Only one factor can be changed in each test Ø Independent (Manipulated) Variable Ø Dependent (Responding) Variable
I. EXPERIMENTAL DESIGN, cont • Setting up a Controlled Experiment, cont o Controlled variables (aka control variables, constants) must be monitored Ø Additional factors that could change from one set-up to another o Sample Size o Minimize potential sources of error o Importance of Repeatable Results • Presentation of Data o Concise & Organized Ø Tables o Graphs Ø Descriptive title Ø Key Ø Units must be evenly spaced (line break) and labeled Ø Use at least half of available space
I. EXPERIMENTAL DESIGN, cont o Graphs, cont Ø DRY MIX Ø Continuous Independent Variable (time) → Line Graph Ø Discrete Independent Variable → Bar Graph Ø Part of a Whole → Pie Graph • Conclusion o Evaluate data Ø Statistical Analysis Ø Null Hypothesis v. Statement of “No Effect” o Address hypothesis Ø Was it supported, refuted, or were results inconclusive? o Assess experimental design • Theory
II. UNITY OF LIFE • Form vs. Function • Characteristics of Life o All living things are made of ______. § §
II. UNITY OF LIFE, cont. • Characteristics of Life, cont o o o o
III. HIERARCHY OF LIFE o Organization of Life Ø Ø Ø § § Ø Ø Ø
III. HIERARCHY OF LIFE, cont • Classification of Life v v v v
III. HIERARCHY OF LIFE, cont • A Closer Look at Classification § Domain ________________ Ø Kingdom ________________________ § Domain ___________________ Ø Kingdom ________________________ Ø Kingdom _______________
III. HIERARCHY OF LIFE, cont • Viruses. . . Living or Nonliving? Ø Discovery of Viruses § First isolated by Ivanowsky in 1890 s from infected tobacco leaves § Crystallized by Stanley in 1935 – proved viruses were not cells Ø Not capable of carrying out life processes without a host cell Ø Parasites
III. HIERARCHY OF LIFE, cont • Viruses, cont Ø Characteristics § Viral genome may be either single-stranded or double-stranded DNA or RNA. § Protein coat surrounding virus is known as a capsid made up of protein subunits called capsomeres. § Some viruses are also surrounded by a viral envelope v. Typically derived from host cell membrane v. Exception is Herpes virus, synthesized from nuclear envelope of host cell v. Aid in attachment. Envelope glycoproteins bind to receptor molecules on host cell
III. HIERARCHY OF LIFE, cont
III. HIERARCHY OF LIFE, cont • Viruses, cont. Ø Bacteriophage § Infect bacteria § Bacterial Defense Mechanisms v. Restriction Enzymes v. Coexistence
III. HIERARCHY OF LIFE, cont – Viral Cycles
III. HIERARCHY OF LIFE, cont – Viral Cycles Viral Entrance into Host Cell
III. HIERARCHY OF LIFE, cont – Viral Cycles LYTIC CYCLE 1. Lytic Cycle – Results in death of host cell.
III. HIERARCHY OF LIFE, cont – Viral Cycles LYSOGENIC CYCLE
III. HIERARCHY OF LIFE, cont – Viruses Retroviruses • Best known example is HIV ØInfects WBCs known as Helper T Cells ØCan reside in lysogenic cycle for years ØActive, symptomatic = AIDS
III. HIERARCHY OF LIFE, cont – Viruses • Coronavirus o o • RNA Envelope Filovirus o o RNA Envelope
III. HIERARCHY OF LIFE, cont – Viruses • Herpesvirus o o DNA Envelope Ø Ø Ø Herpes simplex I and II Epstein-Barr virus Varicella zoster
III. HIERARCHY OF LIFE, cont – Viruses • Influenza Virus o RNA o Envelope • Papillomavirus o DNA • Rhinovirus o RNA
IV. THE DIVERSITY OF LIFE Kingdom Type of Cell Structures Nutrition Description Archaebacteria • • Cell wall not made of _______ Mostly ________ “_______ bacteria”; require ______ conditions Eubacteria • • Cell wall made of ________ Mostly ________ Ubiquitous; _____; may be pathogenic Protista • • Mostly ____ May have cell wall, Auto or hetero chloroplasts, flagella Fungi • • Mostly ____ Cell wall made of ______; no _______! Plantae • • Cell wall made of Strictly All non-motile ______; all ________ have chloroplasts (_______) Animalia • • Never have ____________; chloroplasts “_______”; very diverse “kingdom” Strictly All non-motile; _______________ (_______) Strictly All _______________ during life cycle; (_______) most complex
V. PROKARYOTES – A CLOSER LOOK
V. PROKARYOTES, cont • Archaebacteria Ø Require _______________ Ø Examples include methanogens, thermoacidophiles, halophiles Ø Taq DNA polymerase
V. PROKARYOTES, cont Eubacteria Ø Ubiquitous Ø May be pathogenic • Classification Ø Shape § Cocci § Bacilli § Spirilla Ø Gram Stain Reaction § Positive § Negative
V. PROKARYOTES – EUBACTERIA, cont • Nucleoid region • Plasmids • Asexual reproduction Ø Binary fission
V. PROKARYOTES – EUBACTERIA, cont • Adaptations Ø Capsule § Adherence § Protection § Associated with virulence Ø Pili § Adherence § Conjugation Ø Endospore § Bacterial “hibernation”
V. PROKARYOTES – EUBACTERIA, cont • Adaptations, cont Ø Quorum Sensing/Biofilms § Fairly recent discovery § Bacteria exchange chemical communication signals § Multicellularity? ? ? Ø “Sexual Reproduction” § Transformation § Transduction
V. PROKARYOTES – EUBACTERIA, cont • Adaptations, cont Ø Motility § Flagella § Helical shape § Spirochetes § Slime § Taxis
V. PROKARYOTES – EUBACTERIA, cont Nutrition • Photoautotrophs Ø Photosynthetic Ø Harness light to drive the synthesis of organics Ø Cyanobacteria • Chemoautotrophs Ø Oxidation of inorganics for energy Ø Obtain carbon from CO 2 • Photoheterotrophs Ø Use light to generate ATP Ø Must obtain carbon in an organic form • Chemoheterotrophs Ø Consume organic molecules for both energy and carbon Ø Saprobes - decomposers
V. PROKARYOTES – EUBACTERIA, cont • Metabolism o Nitrogen fixation Ø Conversion of atmospheric nitrogen (N 2) to ammonium (NH 4+) o Metabolic Cooperation Ø Biofilms o Oxygen relationships Ø Obligate aerobes Ø Facultative anaerobes Ø Obligate anaerobes
V. PROKARYOTES – EUBACTERIA, cont Prokaryotic Ecology • Decomposers • Nitrogen Fixation • Symbiosis Ø Commensalism Ø Mutualism Ø Parasitism
V. PROKARYOTES – EUBACTERIA, cont Bacterial Pathogenesis • Koch’s Postulates – Criteria for bacterial disease confirmation Ø The microorganism is found in all individuals with the disease. Ø The microorganism can be cultured from the host. Ø The isolated organism will produce disease when injected into another host. Ø The organism can be isolated from the newly infected host. • Opportunistic Ø Normal residents of host; cause illness when defenses are weakened • Exotoxins Ø Bacterial proteins that can produce disease w/o the prokaryote present (botulism) • Endotoxins Ø Components of gram negative membranes (Salmonella)
EUKARYOTES
VI. KINGDOM PROTISTA • • Very diverse All _________ Mostly _________ Classified according to eukaryotic kingdom protist is most like, nutrition Ø Animal-like § Ingestive § Protozoa Ø Plant-like § Photosynthetic § Algae Ø Fungus-like § Absorptive § Slime Molds
VI. KINGDOM PROTISTA, cont Protist Phylogeny. . . For now!
VI. KINGDOM PROTISTA, cont • Important Protozoans Ø Zooplankton § Important component of aquatic food chains Ø Euglena § § Protozoan or Algae? ? Autotrophic/heterotrophic Pellicle Eyespot; flagella Ø Entamoeba § Intestinal pathogen § Associated with dirty, stagnant water § Moves, feeds using pseudopods Ø Giardia § Lack mitochondria, cell walls § Live in fresh water; flagellated
VI. KINGDOM PROTISTA, cont • Important Protozoans, cont Ø Trypanosoma § Tse-tse fly vector § Blood pathogen; flagellated § Causes sleeping sickness Ø Plasmodium § Belong to Apicomplexa ü All parasitic, non-motile § Cause malaria § Vector = Anopheles mosquito § Resistance seen in _________________
VI. KINGDOM PROTISTA, cont • Algae Ø Very important aquatic producers Ø Phytoplankton Ø Dinoflagellates § Known as “spinning algae” § Red Tides Ø Diatoms § Make up most of Earth’s phytoplankton § Have glass-like silicon shells Ø Foraminiferans § Ca Carbonate shells § White Cliffs of Dover Ø Brown Algae § Kelp
VI. KINGDOM PROTISTA, cont • Algae, cont Ø Rhodophyta § § Red Algae Mostly multicellular Seaweed Also found in coral reefs Ø Chlorophyta § Green Algae v. Volvox v. Spirogyra v. Chlamydomonas § Unicellular; may be colonial § Chloroplasts, cell walls of cellulose § Gave rise to land plants
VI. KINGDOM PROTISTA, cont • Slime Molds
VII. KINGDOM FUNGI
VII. KINGDOM FUNGI, cont • Absorptive heterotrophs; release exoenzymes Ø Decomposers (saprobes) Ø Parasites Ø Mutualistic symbionts (lichens) • Cell Walls Ø Made of ______ • Hyphae Ø Body filaments Ø Network of hyphae known as a mycelium • Primarily reproduce asexually
VII. KINGDOM FUNGI, cont Life Cycle
VII. KINGDOM FUNGI, cont • Important Fungi Ø Rhizopus § Food mold Ø Mushrooms, puffballs, bracket fungi Ø Yeast § Unicellular § Reproduce asexually; budding § May be pathogenic
VII. KINGDOM FUNGI, cont • Specialized Fungi Ø Molds § Used to be classified as Deuteromycota or “Imperfect Fungi” § No known sexual stage § Penicillium Ø Lichens § Mutualistic relationship with algae, cyanobacterium § Sensitive to air pollution Ø Mycorrhizae § Mutualistic relationship found in 95% of all plants § Increases absorptive surface of roots
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