2Classification Taxonomy is: the science of naming and classifying organismsLinnaeus developed a two-word naming systems called binomial nomenclature.Each species is assigned a two-part scientific name.Written in italic, with just the first word capitalizedFirst word: GenusSecond word: speciesFor examples, humans are Homo sapiens
3ClassificationOvertime, Linnaeus’s classification/taxonomy system expanded to organize living things further. This includes:KingdomPhlyumClassOrderFamilyGenusSpecies
5Classification Cladogram- a model used by evolutionary biologists to represent evolutionary history among speciesClade- a group of species that includes a single common ancestor and all descendants of that ancestor.Derived character- a trait that arose in the most recent common ancestor of a particular lineage and was passed along to its descendants.
12Domain Eukarya Examples: Animals, Plants, Fungi, Protists *We will explore each Kingdom in more detail throughout the remainder of the year
13Prokaryotes All bacteria are prokaryotes- unicellular organism that lack a nucleus.small cells (about 1-10 µm) that do not have membrane-bound organellesFound in bacteria and archaebacteria
14Prokaryotes Bacteria Archaebacteria Surrounded by cell wall which contains peptidoglycanArchaebacteriaLook similar to bacteriaLack peptidoglycan in cell wallsLive in harsh environments
15Bacteria Prokaryotic Cell Structures: Nucleoid region – part of the prokaryotic cell where the DNA is foundCell membrane –innermost covering of the cellCell wall –outside of cell membraneCapsule –outside of the cell wall, protective covering (not all bacteria have it)
16Bacteria Prokaryotic Cell Structures (continued): Flagella (sing. Flagellum) –long, whiplike structure that moves bacteriaEndosporeA thick wall that encloses DNA; resistance structure enabling bacteria to survive harsh conditionsPili –short, hair-like projection used to stick to other surfaces and for conjugation (exchange of genetic materials between bacteria)Cytoplasm –jelly-like fluid that dissolves substances and holds organellesRibosomes –organelles that make proteins in the cytoplasm
18Bacterial cell wallsIn bacteria, the cell wall consists of a protein/carbohydrate complex called carbohydrate called peptidoglycan. They are classified based on their cell walls:Gram positive bacteriaMore peptidoglycan in cell wallsAppear purple under the microscope after gram stainGram negative bacteriaHave less peptidoglycan in cell wallsHave outer membraneApper pink under the microscope after gram stain
19Bacteria- shapes Bacilli Cocci Spirilla Rod-shaped Spherical-shaped as either:Staph- clustersStrep-chainsSpirillaSpiral-shaped
21Bacteria- modes of nutrition HeterotrophConsume other organisms: ClostridiumPhotoheterotrophConsume other organisms and can use light energy: RhodobacterPhotoautotrophUse light energy to make carbon compounds; CyanobacteriaChemoautotrophUse chemicals, like ammonia and hydrogen sulfide, to obtain energy; Nitrogen-fixing bacteria
22Bacteria- Aerobic, Anaerobic, and Facultative Anaerobes Need oxygen to liveAnaerobicCannot live with oxygenFacultative anaerobesCan live with or without oxygen
23Bacteria- Binary Fission Process by prokaryotes reproduce by cell division.Steps:Duplication of chromosomes and separation of copies.Cell elongatesDivides into two daughter cells
25Bacteria and DiseasePathology- the study of disease caused by pathogens (microorganism—viruses or prokaryotes– that cause disease)
26Bacteria and diseaseBacteria cause disease by destroying living cells or by releasing chemicals that upset homeostasis.Damaging host tissueReleasing toxins
27Bacteria and Disease Bacteria can be controlled via: Physical removal DisinfectantsFood storageFood processingSterilization by heat
28Bacteria and Disease Bacterial diseases can be treated via- AntibioticsBlocks the growth and reproduction of bacteriaExamples: penicillin, streptomycin, and tetracycline
29Bacteria and Disease Prevention of a bacterial disease via: vaccine- A preparation of weakened or killed pathogens or inactivated toxins that prompt the body to produce immunity to a specific disease upon injection.
30Virus Virus A nonliving particle made of proteins and nucleic acids. Can reproduce only by infecting living cells.Have no cytoplasm or organellesCannot carryout metabolism or homeostasisCan’t grow like cells.
31Virus Viruses consist of… Capsid- protein coat surrounding a virus Some viruses have an envelop that surrounds the capsid (Influenza)Nucleic acids (either DNA or RNA)
33Virus Viral Infections- In order to infect a cell, a virus must be able to recognize it.Viruses must bind the proteins on their capsid specifically to the proteins on their specific host.Viruses then “trick” the cell to take in its genetic material.Viruses will then make multiple copies of themselves inside the cell, ultimately destroying the cell.
34Virus Viral Infections can take place in two ways- Lytic infection Lysogenic infection
35VirusLytic InfectionThe virus infects a cell, it replicates, and the new viruses burst or “lyse” from the cell.
36Virus Lysogenic Infection host cell is not immediately taken over The virus infects a cell, the viral DNA integrates with host DNA where it may stay for a long period of time.The viral DNA multiplies as the host cells multiply.Eventually, it will become lytic, and the viruses will burst from the cell.
37Viruses and DiseaseViruses cause disease by directly destroying living cells or by affecting cellular processes in ways that upset homeostasis. Diseases include:Common coldInfluenzaAIDSChicken poxHepatitisWes Nile VirusHPV (Human papillomavirus)
38Viruses and Disease Ways to fight viruses- Hygiene- Vaccinations Washing hands, avoiding contact with sick individuals, coughing or sneezing into a tissue or your sleeveVaccinationsExposure to inactive forms of the virus that prompt the body to produce immunity to a specific disease upon injection.Vector controlWest Nile Virus is carried by mosquitoes (the vector). Controlling the population mosquitoes could eliminate the spread of the virus.Antiviral drug therapyAttack virual enzymes that in turn slow down or stop the infection cycle of the virus.