Comparison of Genetic Information In Eukaryotes And Prokaryotes
As for organisms in the world from humans to the smallest microbe, they directly reflect upon biodiversity, in respect to the appearance, size and expression. The reason behind this is caused by the genetic material found in each and every cell that composes each organism. Given that there are two types of cell organizations found in life, comparison of both ‘eukaryote’ and ‘prokaryote’ genomes will provide a better understanding for such diversity. ‘karyote’ refers to the nucleus, and also ‘pro’ means ‘absence’ and ‘eu’ means ‘presence’. Therefore the words prokaryote and eukaryote reflect upon the individual cell organization. In contrast, the both organizations show discrepancies as well as similarities which ultimately make them unique to one and other.
The aim of this essay is to compare and contrast the genomes in eukaryotes and prokaryotes according to the perspective of Cell biology (The science that studies about cells). This comparison is conducted on genetic material, in respect to their location, size, expression, structure, architecture as well as number.
Genome Location
The location of genomes in both prokaryotes and eukaryotes show major discrepancies because they have different levels of cell organization. Due to the simplicity of the prokaryotes, they lack membrane bound organelles such the nucleus. Therefore, genomes of the prokaryotes reside as irregular Protein and deoxyribos nucleic acid (DNA) complex in cytosol (liquid portion of cytoplasm). This area of the cytoplasm is defined as the ‘nucleoid’ (Bauman.R 2004). Unlike Eukaryotes, it does not possess a nuclear envelope.
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In conclusion, the above comparison draws out few facts that should be taken into account for a better understanding of the genomes of the two organizations. Above all, the fact that the eukaryotes show similarities to prokaryotes could mean that they derived from prokaryotes initially, and then became more complex as they advanced. This fact also supports the Endosymbiosis theory. And the eukaryotic genomes are larger and more repetitive, which makes them less productive than the prokaryotic genes. But considering by the quantity of the genes, eukaryotes are effective. In the perspective of expression, the complex eukaryotes have to go through physical borders and take more time and energy to express its genes. Due to the simplicity of the prokaryotes, their genomes highly efficient much more simple and they are stronger than what people think.
There are many different cells that do many different things. But all of these cells fall into two categories: prokaryotic and eukaryotic cells. Eukaryotic cells contain a nucleus and are larger in size than prokaryotic cells. Prokaryotic cells do not contain a nucleus, are smaller and simpler than eukaryotic cells. Two of their similarities are they both have DNA as their genetic material and are covered by a cell membrane. Two main differences between these two cells are age and structure. It is believed that prokaryotic cells were the first forms on earth. They are considered primitive and originated approximately 3.5 billion years ago. Eukaryotic cells have only been around for about a billion years. There is strong evidence that suggests eukaryotic cells may be evolved from groups of prokaryotic cells that became interdependent on each other (Phenotypic analysis. (n.d.).
Eukaryotic Cells are Deemed as a Result of the Evolution of Symbiotic Prokaryotes Both Prokaryotic and Eukaryotic cells over time have sustained very dynamic changes from one another. More specifically we have seen the appearance of a more complicated and organized cell structure, the nucleus. However the big question amongst scientists today is how did these changes first occur? A fundamental concept of this evolution is the belief in the natural progression 'from the simple, to the more complex.' However one popular theory that argues that Prokaryotic symbiosis was responsible for forming the Eukaryotic nucleus is the 'Endosymbiotic Theory' this theory was first proposed by a former Boston University Biologist known as Lynn Margulis in the 1960's.
John Philippe Rushton was a Psychology professor at the University of Western Ontario who became generally known for his research on apparent forms of racial variation. Rushton’s book, Race, Evolution, and Behavior (1995), describes his r/k selection theory on how Mongoloids, Negroids, and Caucasoids obtain their evolutionary characteristics. Many critiques and reviews targeted Rushton for his controversial work; including articles from the Behavioral and Brain Sciences (1989). During his early career, Rushton began researching hereditary aspects of altruism; thereby, developing the Genetic Similarity Theory. “Altruism defined as behavior carried out to benefit others, in extreme form altruism involves self-sacrifice. In humans altruistic behavior ranges from everyday kindnesses, through sharing scarce resources, to giving up one's life to save others (Rushton 1989).” This theory was a direct extension of William Donald Hamilton’s Kin Selection Theory. Throughout Rushton’s literature there is a constant pattern of faulty conclusions, citations from his own work, sources that have been outdated, undeterminable measurements, and broad, vague assumptions. The consistency of these complications affected his reputation severely. Rushton appeared to void out any socio-economic factors that could influence his generalizations. Analyzing his Genetic Similarity Theory and evaluating all credible sources, one will find many errors and misconceptions.
The nucleus is one of the most important organelles in a eukaryotic cell. The shape of the nucleus is generally spherical, it should be oval, disc formed reckoning on the sort of cell. The nucleus was found by Robert Brown in 1831 while he was looking at orchids under a microscope. He discovered a blurred area in the cells of the flowers and called it the areola or the nucleus.
... to RNA and the translation to proteins, as well as gene expression. Noble does an excellent job of presenting an opposing view to the central dogma of biology, using metaphors to attempt to make his differing views clearer to the reader. While Noble does use a lot of scientific evidence to support his opinions, his use of metaphors is overwhelming and it can easily distract the reader from the point that he is trying to make. ,Nobles’ explanations of gene expression help the reader to understand the process of evolution, giving a more or less clear view as to how redundancy in the genome can lead to variation. Noble neglects, however, to expand upon natural selection or any other ideas related to evolution. If these ideas were present, they were lost somewhere between the overwhelming use of metaphors and the overly detailed explanations of cell signaling processes.
Transcription occurs within the cytoplasm, and translation also occurs in the cytoplasm within the bacterial cell. However, within the eukaryotic cell the process of transcription occurs within the nucleus and translation occurs within the cytoplasm. The separation of the two processes is due to the fact that the nucleus is where DNA is contained in the eukaryotic cell, and the process of transcription changes the state of mRNA in order to escort the pre mRNA out of the nucleus and into the cytoplasm. During the initiation stage of transcription, the eukaryotic cells have a slightly more complex process. Eukaryotes require multiple transcription factors to bind to the DNA before the RNA polymerase II can attach. The attachment of the multiple transcription factors and the RNA polymerase II enzyme creates the transcription initiation complex, none of which occurs within the bacterial cell. After the transcription process, the eukaryotic cells requires some alteration to the mRNA strand in order to escort it out of the nucleus and into the cytoplasm. The addition of the 5’ cap and the 3’ cap is necessary in order to exit the nucleus; however, none the post-transcription modifications are needed for the bacterial cells. This is due to the previously stated reason of the eukaryotic cell having compartmentalization within the cell, while the bacterial cells have no nucleus holding the cell’s
The two most advanced and scientifically supported hypotheses of evolution from a prokaryote precursor to a eukaryote are The Theories of Endosymbiosis and Autogenesis. The hypotheses both base their claims on the fact that eukaryotic genomes are chimeric, they don’t have a vertical lineage from one common ancestor, but rather a varying ancestry with diverse lineages of archaea and bacteria. Endosymbiosis is the idea that one prokaryotic organism engulfed another which formed a symbiotic relationship between the two, leading to the creation of the eukaryote and its hallmark semi-autonomous organelles (Sagan 1967). Autogenesis is
In the most general terms, the nucleus is the command center of a eukaryotic cell. Although the origin of the organelle is unclear, it is believed that it is derived from a symbiosis relationship between a bacterium and an archaea (Martin W. 2005). Being the main hub for the inner workings of a cell involves different functions overall. These nucleic functions are determined by the genes within the DNA of the cell. Functions of the cell are also regulate by soluble proteins that come in and out of the cell via the membranes and specific channels or the nuclear pore complexes. The overall objectives of the nucleus include; gene expression, compartmentalization, and processing pre-mRNA. The functions of the organelles and sub-regions
Distinct characteristics are not only an end result of the DNA sequence but also of the cell’s internal system of expression orchestrated by different proteins and RNAs present at a given time. DNA encodes for many possible characteristics, but different types of RNA aided by specialized proteins sometimes with external signals express the needed genes. Control of gene expression is of vital importance for an eukaryote’s survival such as the ability of switching genes on/off in accordance with the changes in the environment (Campbell and Reece, 2008). Of a cell’s entire genome, only 15% will be expressed, and in multicellular organisms the genes active will vary according to their specialization. (Fletcher, Ivor & Winter, 2007).
Every cell, either prokaryotic or eukaryotic all contain basic cell parts. They are: a plasma membrane, cytoplasm, DNA (the genetic material), and ribosomes. Prokaryotic cells have a simple structure and they are usually smaller than eukaryotic cells. Also, most prokaryotic cells contain a cell wall. In addition to having the basic cell parts, eukaryotic cells also contain a membrane-bounded nucleus and cell organelles.
Prokaryotic cell: have no membrane covered organelles, they also have circular DNA and bacteria, Eukaryotic cell: have membrane covered organelles, they also have linear DNA and all other cells. Also the cell cycle is short in prokaryotic cells, roughly taking about 20-26 minutes to complete. And in eukaryotic cells, the cell cycle is long, it usually takes about 12-24 hours to complete. Below is a table of some of the differences between the cells:
Discoveries in DNA, cell biology, evolution, and biotechnology have been among the major achievements in biology over the past 200 years with accelerated discoveries and insight’s over the last 50 years. Consider the progress we have made in these areas of human knowledge. Present at least three of the discoveries you find to be the most important and describe their significance to society, heath, and the culture of modern life.
Protists and prokaryotes serve as the primal foundation for the evolution of life present on Earth today. This is exemplified through the endosymbiotic theory, which gave rise to eukaryotic cells, as well as development of photosynthetic processes in plants. Despite the two being quite similar, they also possess key distinguishing features. For instance, the primary difference is that prokaryotes are strictly unicellular organisms, meanwhile protists are able to assume a variety of both multicellular and unicellular forms. Another characteristic of prokaryotes that contrasts with protists is that prokaryotes lack a nucleus and instead merely contain a nucleoid region for unenclosed circular genetic material (Campbell Biology 2017). Each
Perhaps the most readily noticeable characteristic of archaea and bacteria is their size. These domains are comprised of the smallest, self-sustaining forms of life on the planet. Bacteria and archaea are prokaryotic, thus lack a nuclear envelope and membrane-bound organelles. They also present with circular chromosomes, sometimes referred to as “ring-DNA”. Many archaea are known a...
Prokaryotes include several kinds of microorganisms, such as bacteria and cyanobacteria. Eukaryotes include microorganisms as fungi, protozoa, and simple algae. Virus cells often consist of just a nucleic acid either DNA or RNA in a protein capsule. Viruses are considered neither prokaryotes nor eukaryotes because they lack the characteristics of living things, except the ability to replicate (which they accomplish only in living cells).