Presentation on theme: "Classification of organisms"— Presentation transcript:
1Classification of organisms Kingdoms: Eubacteria, Archaebacteria, Protist and Fungi
2classificationGrouping objects or organisms based on a set of conditions.For biologists, doing this with all of the organisms there are on the earth, it makes it easier to study them!There are many different ways to group organisms.
3Early systems of classification Aristotle: plant or animalThen animals were further classified based on habitat and physical characteristics.Plants were further classified by size and structure, trees, shrubsThis system did NOT take into account the changes and evolutionary history of the organisms.
4New systems of classification In the 18th centuryCarolus Linnaeus developedTaxonomyA branch of biology concerned with naming, identifying and classifying species based on morphological and behavioral similarities and differences.Linnaeus gave each organism 2 namesA genus and a species name and called this binomial nomenclature.
5Taxonomy A systematic method of classifying plants and animals.Classification of organisms based on degrees of similarity representing evolutionary (phylogenetic) relatedness.
6Scientific Names Binomial nomenclature (Linnaeus) A 2 name system so that not two organisms will ever have the same name.The genus name is combined with a second name to make the species name unique.For example: humansGenus HomoSpecies Homo sapiens
7Why 2 names? The name are Latin ( the language of science) The first is the genusThe second is the epithet or specific identifying name. They are both needed to identify the organism.Common names can vary but scientific are universal.First names are capitalized, second are not.In books, names are italicized, if hand written they are underlined.The genus can be abbreviated with the first letter
8Human classification Kingdom Animalia Phylum (Division for plants) ChordataClass MammaliaOrder PrimatesFamily HominidaeGenus HomoSpecies Homo sapiens
9Levels of classification King Philip came over from Germany swimmingCLASSKINGDOMORDERPHYLUMFAMILYGENUSSPECIESSMALLESTLARGEST
10Domains The largest groups Eukarya Archaea/ Archaebacteria Bacteria/Eubacteria
11Each level has more and more similarities! DomainKingdomPhylum (Division for plants)ClassOrderFamilyGenusSpecies
13How has classification changed? Today classification looks at the evolutionary relationships and DNA similarities.Many organisms have been reclassified from where they were originally classified as new information is learned.
14genusA groups of organisms that are closely related and share a common ancestor.
15familyA group of genera that have similar characteristics
16speciesOrganisms so closely related that they can mate and produce fertile offspring in a natural setting.The “biological species concept”There are exceptions to this definition but it works for most organisms.Phylogenetic species: goes with biologic and says the organisms have evolved independently from an ancestral population.
17phylogeny The evolutionary history of a species. Where did it come from?When organisms become isolated they become different, this can lead to new species…
18characters Inherited features that vary among species Used by scientists to help put together the evolutionary history of a species: its phylogeny.The more shared characters/the more closely related.Homologous structures show relationshipsAnalogous structures don’t
20Dinosaurs and birds Oviraptor and sparrow Feathers, hollow spaces in bones similar bone structures to birds show more similarities to dinosaurs with birds then to reptiles.
21DNA sequencesThe more similar the sequences, the closer the relationship between the organisms.
22Molecular clocksMutations occur randomly and can be used to determine how long the DNA has been mutating or changing from its original form.A major problem with this includes the fact that the genes don’t mutate at a constant rate!These are used to try to determine when a divergence from a common ancestor occurred.
23cladistics A way to study evolutionary relationships. It rebuilds phylogenies and hypothesizes evolutionary relationships using shared characters.Cladograms show branching diagrams where each species may have originated.Kind of like a pedigree!
30Kingdoms/Domains Archaea (Archaebacteria) and Bacteria (Eubacteria)
31Archaea /Archaebacteria ProkaryoticUnicellularNo nucleusNo peptidoglycan on the cell wallsSome similarities to eukaryotes in the cytoplasmSome Autotroph/ most heterotroph
32ArchaebacteriaThe most primitive group, the archaebacteria, are today restricted to marginal habitats such as hot springs or areas of low oxygen concentration.Three types of Archaebacteria: methanogens, halophiles, and thermacidophiles.They live in extreme habitats like very salty water!prokaryotes
33Domain and Kingdom Bacteria/Eubacteria prokaryotes unicellular no nucleus cell walls contain peptidoglycan some autotrophs/ most heterotrophs
34Organisms in this group lack membrane-bound organelles associated with higher forms of life. Such organisms are known as prokaryotes.Their small size, ability to rapidly reproduce (E. coli can reproduce by binary fission every 15 minutes), and diverse habitats/modes of existence make bacteria the most abundant and diversified kingdom on Earth.
35Bacteria occur in almost every environment on Earth, from the bottom of the ocean floor, deep inside solid rock, to the cooling jackets of nuclear reactors.
36Rod-Shaped ( Bacillus) Bacterium, hemorrhagic E. coli, strain 0157:H7
37Scanning electron micrographs illustrating external features of the rod-shaped bacterium E. coli.
40Left, a cross-section of a cell illustrating the location of a flagella inside the cell; Center, Borrelia burgdorferi, the organism that causes Lyme disease; and Right, Treponema pallidum, the spirochete that causes the venereal disease syphilis. The image above is from
44Endosporesare a method of survival, not one of reproduction. Certain bacteria will form a spore within their cell membrane (an endospore) that allows them to wait out deteriorating environmental conditions.Certain disease causing bacteria (such as the one that causes the disease Anthrax) can be virulent (capable of causing an infection) 1300 years after forming their endospores
45All other Kingdoms are made up of Eukaryotic cells Domain EUKARYA HAVE ORGANELLES A NUCLEUS
46Evolution of Eukaryotes The endosymbiosis hypothesis…
47PROTISTS ?? eukaryotic unicellular/ some multi heterotrophic and autotrophic
48New classification??Some plant like some animal like.This is a great example of how the system is constantly changing based on new information!!!
49Classification of Protists The protists include heterotrophs, autotrophs, and some organisms that can vary their nutritional mode depending on environmental conditions.Protists occur in freshwater, saltwater, soil, and as symbionts within other organisms.Due to this tremendous diversity, classification of the Protista is difficult.
50Protozoa: Single-Celled, Motile Organisms “animal-like” This group of protists are single-celled, motile, heterotrophs.Most digest their food by vacuoles formed by phagocytosing other organisms (bacteria or other single-celled creatures).Reproduction varies greatly, from a binary fission-like process to true meiosis.The main distinguishing feature is the method of locomotion: flagella, cilia, or pseudopodia.
51Amoeboid Protozoa Use Pseudopods for Movement Amoeba and Pelomyxa move by extensions of their cytoplasm known as pseudopodia.
52Foraminiferalive in the oceans and secrete a shell (also known as a test) composed of silica or calcium carbonate.Thus, the fossil record of forams is quite good. Oxygen isotope data from forams has been used to calculate ocean temperature fluctuations over the past 100,000 years.
53Sporozoans Members of this group cause malaria and toxoplasmosis. Toxoplasmosis is transmitted from cats to humans, with between 7 and 72% of the population infected, depending on the geographic area.
54Malariainfects an estimated 300 million people, and is spread by mosquitoes, transfusions, and shared hypodermic needles.Infected individuals can be treated with a variety of medicines. However, some of the sporazoans that cause malaria have developed immunity to some of the more commonly employed medicines.
56CiliatesCiliates are complex, heterotrophic protozoans that lack cell walls and use multiple small cilia for locomotion.To increase strength of the cell boundary, ciliates have a pellicle, a sort of tougher membrane that still allows them to change shape.Most of the 8000 species are freshwater. Most ciliates have two nuclei: a macronucleus that contains hundreds of copies of the genome and controls metabolisms, and a single small micronucleus that contains a single copy of the genome and functions in sexual reproduction.
64Red tidesare caused by population explosions of certain dinoflagellates that release a neurotoxin into the environment.Shellfish concentrate this toxin and it can kill people who eat the contaminated shellfish.
69FUNGI eukaryotic unicellular and multicellular heterotrophic chitin in cell walls can’t move! Live in many environments
70FungiFungi are almost entirely multicellular (with yeast, Saccharomyces cerviseae, being a prominent unicellular fungus), Bread yeast
71heterotrophic (deriving their energy from another organism, whether alive or dead), and usually having some cells with two nuclei (multinucleate, as opposed to the more common one, or uninucleate) per cell.
72Ecologically this kingdom is important (along with certain bacteria) as decomposers and recyclers of nutrients.Economically, the Fungi provide us with food (mushrooms; Bleu cheese/Roquefort cheese; baking and brewing), antibiotics (the first of the wonder drugs, penicillin, was isolated from the fungus Penicillium), and crop parasites (doing several million dollars per year of damage).
74Structures in the bodies of fungi Hyphae: filamentsFruiting bodies: reproductive structuresCell walls made up of chitinMycelium: net like mass of hyphae
75Beer and wine are produced through the action of fungi known as yeasts, such as Saccharomyces cerviseae.Many antibiotics are produced by fungi.
76Fungi are important both as a source of food and in the preparation of food. Edible fungi include mushrooms, truffles, and morels. Cheeses such as Gorgonzola, Roquefort, Stilton, and bleu have fungal colonies that give theses cheeses their distinctive flavors.
78Classification of Fungi Over 60,000 species of fungi are known. Fungi are classified by their method of reproduction (both sexual and asexual).Historically they have been divided into four taxonomic divisions: Chytridiomycota (chytirids), Zygomycota (mold), Ascomycota (Yeast or sac fungi), Basidiomycota (club mushrooms), and Deuteromycota (imperfect).
79Mutualistic symbiotic fungal relationships Lichens: fungus and algaeMycorrhizae: fungus and plant roots
80Genus: Candida Disease(s): Candidiasis Image Legend: Skin scraping from superficial candidiasis showing clusters of budding yeast cells and branching pseudohyphae.
81Club fungi are important as commercial crops Club fungi are important as commercial crops. They also cause many diseases that result in loss or reduction of grain yields.Agaricus campestris is the common mushroom found in grocery stores;Lentinus edodes is the less commonly bought shitake mushroom: more than $14 billion per year of these products are sold.
82Amanita phalloides is the most poisonous of all mushrooms Amanita phalloides is the most poisonous of all mushrooms. Other mushrooms have hallucinogenic properties (such as the drug psilocybin) important in native religious rituals in Central and South America.
84Genus: Epidermophyton Species: floccosum Disease(s): Athlete's foot Title: Tinea pedis Image Legend: The disease is unusual because the nails are also involved.
85Genus: Trichophyton Species: verrucosum Disease(s): Dermatophytosis, Tinea barbae Title: Dermatophytosis of the beard area Image Legend: Severe tinea barbae caused when the patient rubbed against cattle.
103RetrovirusesRetroviruses have RNA and the enzyme reverse transcriptase instead of DNA as their nucleic acid core.Once inside the host cell, reverse transcription (making DNA from RNA) is accomplished by the reverse transcriptase, turning the single-stranded RNA into DNA. This new DNA is incorporated into the host DNA, where it transcribes new viral RNA genomes, as well as the RNA to synthesize new reverse transcriptase and protein capsules.
104Viruses are usually quite specific as to their hosts and even to the types of cells they infect in a multicellular host.Viruses can NOT be treated with antibiotics because antibiotics are designed to attack the cell wall or membrane and viruses do not have these!
105Viroids and PrionsViruses would appear to be the simplest form of infectious particle.The discovery of viroids, nucleic acid without a protein capsule and prions, infectious proteins, subtracts another level of complexity.Both viroids and prions can cause diseases.
106Review sheet 1. What is taxonomy? It is a systematic method of classifying plants and animals.2. What is binomial nomenclature?It is a 2 name system so that no two organisms will ever have the same name.3. Who is the person who came up with the 2 name system?(Linnaeus)
1074. What are the levels of classification from least to most specific? Kingdom , Phylum (Division for plants) , Class, Order , Family , Genus , Species5. Name the 6 kingdomsArchaebacteria, Eubacteria, protist, fungi, plant, animal
1086. Are viruses alive? Why or why not? Viruses are NOT one of the 6 kingdoms and are not considered “alive” because they are not made up of cells, do not metabolize, can only reproduce inside another living cell and do not grow.7. What is a virus?A virus is a submicroscopic infectious particle composed of a protein coat and a nucleic acid core.8. Can viruses be treated with antibiotics?Viruses can NOT be treated with antibiotics because antibiotics are designed to attack the cell wall or membrane and viruses do not have these!
1099. What are the characteristics of the kingdom Archaebacteria? Prokaryotic, Unicellular, Autotroph/ heterotroph10. What are examples of A bacteria? Where do you often find them?Three types of Archaebacteria: methanogens, halophiles, and thermacidophiles.They live in extreme habitats like very salty water!11. Describe EubacteriaProkaryotes, unicellular, autotroph/heterotroph
11012. What are the three main shapes of bacteria? Round, cocci, Rod, bacilli, Spiral, spirilli13. What is binary fission? Cell divisionWhy do bacteria use this? Bacteria can reproduce by binary fission14. Describe the Protist kingdom.Eukaryotic, unicellular/ some multi, heterotrophic and autotrophic
11115. List some examples of protists Euglena, amoeba, red algae16. Describe the FUNGI kingdom eukaryotic, multicellular, heterotrophic, chitin in cell walls17. List some examples of fungi.Mold, athletes foot, mushrooms