Lab 10 Classification of OrganismsComplete your answers in the spaces provided. Remember to add your last name and first initialto the file name prior to saving and submitting your completed assignment through Canvas.Background:All knowledge is sorted and organized so that new discoveries can be recognized as somethingnew that has never been seen and understood before. This organization of knowledge pervadesall different content. This is not something new that we in the modern era have developed. CarlLinneaus (1707-1778) came up with the basis of the modern system of classification of all livingorganisms. His taxonomic system is based on grouping organisms by their similarities. Themore similar organisms are to one another the more closely they will be in taxonomicclassification. The most specific level of his classification is the species.The most general level of classification is the Domain and progressing in specificity isKingdom Class Order Family Phylum Genus Species. Believe it or not classification is oneof the most contentious specialties in biology. The more organisms whose DNA is sequencedthe more things change as genetic sequence similarities are used to group organisms together asopposed to grouping them by structural and functional similarities. Currently there are severalclassification schemes with varying numbers of Kingdoms.The most specific level of classification is that of the species. At the species level all organismsof the same species must be able to mate with one another and produce viable offspring – that isoffspring who themselves can mate and produce viable offspring. When you mate a horse anddonkey their offspring is a mule. But you cannot mate two mules with one another – mules aresterile. This means that horses and donkeys are each a unique species.Moving up in the hierarchy towards Domain the organisms are less and less alike one another.In current taxonomic classification we have three Domains. Dr. Carl Woese studied the rRNAsequences and structures of organisms and found there were three distinct types of rRNA. TheDomains are distinguished from one another by this difference. The three domains are Archaea Eubacteria and Eukaryotes. While both the Archaea and Eubacteria are prokaryotic organismswithout their DNA enclosed by a membrane bound nucleus they are still separated from oneanother by the difference in their rRNA sequences and structures. The third Domain is theEukaryotes whose members all have their DNA sequestered from the rest of their cells by anuclear membrane. Eukaryotes also have other membrane bound organelles.As you move down from the Domain level to the Species level the characteristics becomeincreasingly more specific. The focus of this lab is on the three Domains (Eubacteria Archaea and Eukaryota) and four of the Kingdoms in the Eukaryotic Domain: Protista Plantae Fungi and Animalia. Page 1 of 7 Depending onthe classificationscheme eachbranch of thethree Domainsmay or may notbe considered aKingdom. Here are some of the most common and useful characteristics used in classification:Symmetry is a component of physical organization of an organism. There are three options forsymmetry: None Bilateral or Radial. Symmetry applies equally to both animals plants fungi and protists.No symmetry means there is no overall organization of the physical exterior of the organism.Bilateral … Bi = two and Lateral = sides … so two sides. A bilateral organism has a definite leftand right side. Only one plane divides the organism into left and right halves.Radial – Like a wheel any plane that travels from one side to the other through the absolutecenter will divide the individual into left and right halves.All organisms require some type of structural support – the more complicated the physicalorganism the more structural support that is usually necessary. Structural support can be internal(endoskeleton) or external (exoskeleton). Internal bony or cartilaginous structural support is anendoskeleton while shells that have to be replaced as an organism grows are an example of anexoskeleton.The method of obtaining energy also is part of classification. Organisms are either self feeding(autotrophs) by extracting energy from raw chemical materials (chemotrophs) or from the sun(phototrophs/photosynthesis) or they must feed on other organisms for energy (heterotrophs).Heterotrophs are further separated from one another by the actual method they use to consumeother organisms. They can absorb nutrients directly through their plasma membranes or theycan ingest (eat) and digest organisms.Page 2 of 7 Then there are the mixotrophs …. HUH??? These are organisms which live together in asymbiotic relationship. Two or more different species contribute to the survival of bothorganisms. Coral is an example of this arrangement. Many corals have photosyntheticorganisms which benefit from the protection of living within the corals and the corals which arefilter feeders also gain additional nutrients from the products of the algal photosynthesis of theirsymbiots. So while the algae living within the coral are photosynthetic autotrophs and the coralpolyps on their own are heterotrophs the symbiotic pair is a mixotroph.Segmentation consists of a body with similar repeating parts. The most obvious example ofsegmentation is seen in the Annelid phylum which includes earth worms and leeches. Theseorganisms have identical segments from their head end to the end of their bodies. Here each individual band is asegment of the worm and isseparated from adjacent segments bya thin layer of tissue. Each bandcontains a section of body wall andindividual internal structures. Other phyla have varying levels of segmentation. Notably the Arthropods which include insects lobsters and shrimp have body plans that are obviously delineated into organized shelled regionseach with a specific purpose. It is easiest to see this when looking at the thorax which hasrepeating segments all including a leg. Each arrow ispointing to thebase of a leg.Each leg pairis attached atthe base of asegment. Page 3 of 7 Nervous systems allow an organism to control what they do where they go and any decisionmaking they may or may not be able to do. At the simplest end of the spectrum sea sponges donot have neurons nor a nervous system but their cells do communicate via calcium waves tocontrol simple things such as whole body contractions. Jelly fish utilize a nerve net. They havesensory cells that are spread out across their bodies along with motor neurons which allow thesecreatures to move towards or away from a variety of stimuli. The most advanced nervous systemis the nerve cord linked to ganglia (groups of nerve cells) which is found in organisms ragingfrom insects up through advanced vertebrates. These nervous systems have sensory and motornerve cells which provide the ability to sense and respond to a significant number of stimuli. A”brain” is the developed anterior section of a nerve cord seen in higher order organisms whichgive them the ability to discern ever more complex stimuli participate in more advancedcommunication and actual learning.Pre Lab Matching: Use the choices (A-Y) below to complete question. Choose the BESTanswer to complete the statements. 1 point each.A.B.C.D.E.F. AutotrophHeterotrophChemotrophPhotosynthesisCellular respirationProkaryotes G. EukaryotesH. ProtistaI. AnamaliaJ. FungiK. PlantaeL. Annelid M. PeptidoglycanN. SymbioticO. HydrocarbonsP. HydrophobicR. AbsorptionS. Eubacteria T. CelluloseU. KeratinV. ChitinW. HydrophillicX. MixotrophicY. Archaea ChoiceUPPEREntire Word or Phrase … Normal caseCASE11. Eubacteria are classified asand have cell walls containing 2 2. Archaea are classified as 3 3. have a membrane bound nucleus and/or organelles 4 4. live in extreme environments. 5 6 and have cell walls containing 5/6. Plants have cell walls made of (5) while fungi have cell walls made of (6)Page 4 of 7 7 7. 8 8. Fungi use 9 9. 101112 13 are among the oldest organisms on Earth.to obtain nutrientsare organisms which do not fit in other eukaryotic categories. 10. Plants are classified as because they make their own food. 11. Which Kingdom(s) have organisms which can move on their own? List all thatapply12. Corals are an example of a/an (12)due to their (13) living arrangement with algae. Open the pdf file of images from the canvas assignment page anduse them to complete the rest of this assignment.14. Identify the samples possessing radial symmetry by sample number. 15. Identify the samples possessing an endoskeleton by sample number. 16. Which samples EQXPEHUare examples of secondary consumers with bilateral symmetry? 17. Which samplesEQXPEHU illustrate segmentation and an exoskeleton? 18. Which samplesEQXPEHU are autotrophs? Page 5 of 7 Table 2 Phyla of the Animal KingdomAnimalia PhylumPorifera Sea Life SymmetryNone Cnidaria Radial Mollusca Bilateral Platyhelminth Bilateral Nematode Bilateral Annelid Bilateral Invertebrates Arthropod Bilateral Vertebrates Chordate Bilateral Worms Additional Characteristics- No nervous digestive orcirculatory systems- Filter feeders- True tissue differentiationand nematocyts- True coelom- Soft body; some secrete calcium based shell- Unsegmented- Nervous system and true organs- Single opening to digestive tract- Unsegmented- Nervous anddigestive system- Segmentation- Nervous digestive andcirculatory systems- Segmentation- Exoskeleton- Circulatory system- Endoskeleton- Nervous digestive andcirculatory systems Page 6 of 7 Using the following characteristics determine the phylum for the chosen samplesSymmetry; None Bilateral RadialEnergy acquisition; Autotroph Heterotroph ingestion/digestion Heterotroph absorptionBody plan; Segmented or Not segmentedSupport; Endoskeleton Exoskeleton; Soft-bodiedNervous system; None Nerve net Nerve Cord For the sample listed determine the phylum. Include the characteristics from the list abovefor each sample.Sample SymmetryEx. 4 19 3 20 6 21 10 22 1 23 Bilateral EnergyNervousBody PlanSupportAcquisitionSystemHeterotroph Segmented Exoskeleton NerveIngestionCord PhylaArthropod Page 7 of 7
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