Eukaryotic CellProkaryotic CellHide AllShow All

Microtubules:PresentAbsent or rarehide

Vesicles:PresentPresenthide

Mitochondria:PresentAbsenthide

Chloroplasts:Present (in plants)Absenthide

Plasma membrane with steriod:YesUsually nohide

Golgi apparatus:PresentAbsenthide

Endoplasmic reticulum:PresentAbsenthide

Differentation:Tissue and organsRadimentaryhide

Ribosomes:80S especially in Mitochondria and chloroplast70Shide

Cytoskeleton:PresentMay be absenthide

Vacoules:PresentPresenthide

Number of chromosomes:More than oneOnehide

DNA complexed histones:YesNohide

True Membrane bound Nucleus:PresentAbsenthide

Cell wall:Chemically simplerUsually chemically complexedhide

Nucleolus:PresentAbsenthide

Mitosis Occurs:YesNohide

Genetic Recombination:Mitosis and fusion gametesPartial, undirectional transfers DNAhide

Flagella:Microscopic in size; membrane bound; usually arranged as nine doublets surrounding two singletsSubmicroscopic in size, composed of only one fiberhide

Lysosomes and peroxisomes:PresentAbsenthide

All cells can be classfied into prokaryotes and eukaryotes. Prokaryotes were the only form of life on Earth for millions of years until more complicated eukaryotic cells came into being through the process of evolution.Contents[hide] 1 Definition of eukaryotes and prokaryotes 2 Differences between eukaryotic and prokaryotic cells 3 Video comparing Eukaryotic Cell and Prokaryotic Cell 4See Also

[edit] Definition of eukaryotes and prokaryotes Prokaryotes (pro-KAR-ee-ot-es) (from Old Greek pro- before + karyon nut or kernel, referring to the cell nucleus, + suffix -otos, pl. -otes; also spelled "procaryotes") are organisms without a cell nucleus (= karyon), or any other membrane-bound organelles. Most are unicellular, but some prokaryotes are multicellular).Eukaryotes (IPA: [jukt]) are organisms whose cells are organized into complex structures by internal membranes and a cytoskeleton. The most characteristic membrane bound structure is the nucleus. This feature gives them their name, (also spelled "eucaryote,") which comes from the Greek , meaning good/true, and , meaning nut, refering to the nucleus. Animals, plants, fungi, and protists are eukaryotes.[edit] Differences between eukaryotic and prokaryotic cells The difference between the structure of prokaryotes and eukaryotes is so great that it is considered to be the most important distinction among groups of organisms.

Structure and contents of a typical Gram positive bacterial cell (a prokaryotic cell) The most fundamental difference is that eukaryotes do have "true" nuclei containing their DNA, whereas the genetic material in prokaryotes is not membrane-bound. In eukaryotes, the mitochondria and chloroplasts perform various metabolic processes and are believed to have been derived from endosymbiotic bacteria. In prokaryotes similar processes occur across the cell membrane; endosymbionts are extremely rare. The cell walls of prokaryotes are generally formed of a different molecule (peptidoglycan) to those of eukaryotes (many eukaryotes do not have a cell wall at all). Prokaryotes are usually much smaller than eukaryotic cells. Prokaryotes also differ from eukaryotes in that they contain only a single loop of stable chromosomal DNA stored in an area named the nucleoid, while eukaryote DNA is found on tightly bound and organised chromosomes. Although some eukaryotes have satellite DNA structures called plasmids, these are generally regarded as a prokaryote feature and many important genes in prokaryotes are stored on plasmids. Prokaryotes have a larger surface area to volume ratio giving them a higher metabolic rate, a higher growth rate and consequently a shorter generation time compared to Eukaryotes. Genes Prokaryotes also differ from eukaryotes in the structure, packing, density, and arrangement of their genes on the chromosome. Prokaryotes have incredibly compact genomes compared to eukaryotes, mostly because prokaryote genes lack introns and large non-coding regions between each gene. Whereas nearly 95% of the human genome does not code for proteins or RNA or includes a gene promoter, nearly all of the prokaryote genome codes or controls something. Prokaryote genes are also expressed in groups, known as operons, instead of individually, as in eukaryotes. In a prokaryote cell, all genes in an operon(three in the case of the famous lac operon) are transcribed on the same piece of RNA and then made into separate proteins, whereas if these genes were native to eukaryotes, they each would have their own promoter and be transcribed on their own strand of mRNA. This lesser degree of control over gene expression contributes to the simplicity of the prokaryotes as compared to the eukaryotes.[edit] Video comparing Eukaryotic Cell and Prokaryotic Cell [edit] See Also Plant cells vs. Animal cells Difference between DNA and RNA Bacteria vs Virus Meiosis vs Mitosis Xylem vs Phloem ACT vs SATCategories: Cellular Biology | Microbiology | Molecular Biology | Biology | ScienceFollow Diffen.com:Share this comparison:[Add Comments]Comments: Eukaryotic Cell vs Prokaryotic CellComments on Eukaryotic Cell vs. Prokaryotic Cellsince eukaryotic cells have operons as well, im disinclined to agree with the statement that operons contribute to the simplicity of prokaryotes.- by 192.17.178.254 on 2010-10-15 15:16:32I'm trying to figure out why there is such differences in sizes between the cells.- by 68.217.211.138 on 2009-03-21 00:54:24Also on Diffen Compare CamerasCompare Cell PhonesCompare Processorsmore..

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The hierarchy of biological classification's eight major taxonomic ranks, which is an example of definition by genus and differentia. Intermediate minor rankings are not shown.A prefix is used to indicate a ranking of lesser importance. The prefix super- indicates a rank above, the prefix sub- indicates a rank below. In zoology the prefix infra- n.com/difference/Eukaryotic_Cell_vs_Prokaryotic_Cell#ixzz1MEoEjhsJ

Modern bird orders: ClassificationSee also: List of birdsNeornithes Palaeognathae Struthioniformes

Tinamiformes

Neognathae Other birds (Neoaves)

Galloanserae Anseriformes

Galliformes

Basal divergences of modern birdsbased on Sibley-Ahlquist taxonomy

Cladogram showing the most recent classification of Neoaves, based on several phylogenetic studies.[27]This is a list of the taxonomic orders in the subclass Neornithes, or modern birds. This list uses the traditional classification (the so-called Clements order), revised by the Sibley-Monroe classification. The list of birds gives a more detailed summary of the orders, including families.Subclass NeornithesThe subclass Neornithes has two superorders Superorder Palaeognathae:The name of the superorder is derived from paleognath, the ancient Greek for "old jaws" in reference to the skeletal anatomy of the palate, which is described as more primitive and reptilian than that in other birds. The Palaeognathae consists of two orders which comprise 49 existing species. Struthioniformesostriches, emus, kiwis, and allies TinamiformestinamousSuperorder Neognathae:The superorder Neognathae comprises 27 orders which have a total of nearly ten thousand species. The Neognathae have undergone adaptive radiation to produce the staggering diversity of form (especially of the bill and feet), function, and behavior that are seen today.The orders comprising the Neognathae are:

Moa attacked by a Haast's Eagle Anseriformeswaterfowl Galliformesfowl Charadriiformesgulls, button-quails, plovers and allies Gaviiformesloons Podicipediformesgrebes Procellariiformesalbatrosses, petrels, and allies Sphenisciformespenguins Pelecaniformespelicans and allies Phaethontiformestropicbirds Ciconiiformesstorks and allies CathartiformesNew World vultures Phoenicopteriformesflamingos Falconiformesfalcons, eagles, hawks and allies Gruiformescranes and allies Pteroclidiformessandgrouse Columbiformesdoves and pigeons Psittaciformesparrots and allies Cuculiformescuckoos and turacos Opisthocomiformeshoatzin Strigiformesowls Caprimulgiformesnightjars and allies Apodiformesswifts and hummingbirds Coraciiformeskingfishers and allies Piciformeswoodpeckers and allies Trogoniformestrogons Coliiformesmousebirds PasseriformespasserinesThe radically different Sibley-Monroe classification (Sibley-Ahlquist taxonomy), based on molecular data, found widespread adoption in a few aspects, as recent molecular, fossil, and anatomical evidence supported the Galloanserae.[23]