Prokaryotes and Eukaryotes are the two fundamental or basic classes of cells. They are mainly distinguished by their size and internal structures. The existence of two classes of cells without any intermediate type represents one of the most fundamental evolutionary separations in the living world. Prokaryotes are structurally and evolutionarily more primitive to eukaryotes. Even though they are two separate classes of living organisms, they share many common characteristics. The shared properties reflect the fact that eukaryotic cells most certainly evolved from prokaryotic ancestors. Shared common characters of prokaryotes and eukaryotes are as follows: (1).

Cellular contents in both prokaryotes and eukaryotes are limited by plasma membrane (2). In both groups, plasma membrane composed of lipid bilayer with intermittent protein molecules (3). DNA is the genetic information carrier in both the groups (4). Chemical composition of nucleic acids (DNA and RNA), their structure and their organization are similar in both groups (5). Even though the mechanism slightly varies, the process of transcription, translation and DNA replication occurs in both prokaryotes and eukaryotes (6). Both groups processes regulation of expression of genetic information. MRNA acts as the intermediate molecule between genetic information and their expression (as proteins) in both groups (8).

Proteins are the expression of genetic information in both groups (9). All the 20 protein coding amino acids are similar in prokaryotes and eukaryotes (10). All the 61 codons are similar in both groups (11). All the tree stop codons (UAA, UAG, UGA) are similar in both groups (12). Structure of tRNA is similar in both groups (13).

Metabolic pathways such as glycolysis and TCA cycle are similar in both prokaryotes and eukaryotes (14). In both groups, the metabolic pathways are multi-step processes each step catalyzed by specialized proteins called enzymes (15). ATP is the energy currency in both prokaryotes and eukaryotes (16).

ATP is produced by the use of proton (H+) gradient, which is similar in both groups (17). Photosynthesis is similar in both prokaryotes (blue green algae) and eukaryotes (plants) (18). In both forms, photosynthesis consists of two process, light dependent ‘light reaction’ and light independent and ‘dark reaction’ (19). Proteasomes are with similar structure and working in both groups Thus the overall biological process, events and organization are similar in both prokaryotes and eukaryotes. Arma 2 How To Install Vte Modular. Craigslist Cash Cow Pdf Viewer. However each component and their interactions to each other vary in both groups.

Comparison of DNA polymerases from prokaryotic and eukaryotic origin showed extensive amino acid homology in addition to highly conserved domains. These findings reflect. Get a printable copy (PDF file) of the complete article (2.1M), or click on a page image below to browse page by page.

The major differences between Prokaryotes and Eukaryotes are summarized in the following table:. Prokaryotes Eukaryotes 1 ‘pro’ = pre, ‘karyon’= nucleus ‘eu’ = true, ‘karyo’ = nucleus 2 Originated about 3.5 billion years ago Originated about 1.2 billion years ago 3 Primitive forms Advanced forms 4 Usually unicellular organization Usually multicellular organization 5 Incipient nucleus, true nucleus absent True nucleus present 6 Small cell size, usually 1 – 10 µm Larger cell size, usually 5 – 100 µm, sometimes very large and macroscopic 7 Membrane bounded organelles such as nucleus, mitochondria, Golgi bodies, chloroplasts, lysosome, peroxisomes, ER etc. Are absent Membrane bounded organelles present.

› › › The distinction between prokaryotes and eukaryotes is considered to be the most important distinction among groups of organisms. Eukaryotic cells contain membrane-bound organelles, such as the nucleus, while prokaryotic cells do not. Differences in cellular structure of prokaryotes and eukaryotes include the presence of mitochondria and chloroplasts, the cell wall, and the structure of.

Prokaryotes were the only form of life on for millions of years until more complicated eukaryotic cells came into being through the process of evolution. Structure and contents of a typical cell (a prokaryotic cell) • In eukaryotes, the mitochondria and chloroplasts perform various metabolic processes and are believed to have been derived from endosymbiotic. 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 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 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 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 contributes to the simplicity of the prokaryotes as compared to the eukaryotes. References • •.