Over evolutionary time, they and their DNA became integrated into the cell to form a new type of life called eukaryotes. Endosymbiosis suggests that certain organelles were once free living organisms that were taken into larger cells and the arrangement was beneficial to both organisms. First off, mitochondria and chloroplasts are similar in size and morphology to bacterial prokaryotic cells, though the mitochondria of some organisms are known to be morphologically variable. Also, mitochondria and chloroplasts divide by binary fission, just as bacteria do, and not by mitosis as eukaryotes do. Additionally, the DNA of mitochondria and chloroplasts are different from that of the eukaryotic cell in which they are found.
Answer: Intermediate filaments are similar to microtubules and microfilaments in which they all have a similar shape, and function, and all three are what make up the cytoskeleton. However they are different in which they each consist of different proteins. 8) What advantage does compartmentalization provide to a large and complex cell? Answer: Compartmentalization separates biochemical that can harm certain cells. Compartmentalization also organizes the cell so it can function more efficiently.
First, they are capable of renewing themselves through cell division. Secondly, they can be introduced to become tissue or organ-specific cells with specific functions to divide and repair worn or damaged tissues. Stem cells are important because they are undifferentiated, or initially have no specific physiological function. Hence the name-every cell in the body ‘stems’ from a stem cell. It isn’t until the stem cell receives a signal, that it begins to differentiate or gradually change into one of the two hundred or more types of cells that it is destined to be.
Eukaryotes are much more complex than prokaryotes and contain many membrane bound organelles and much more internal organisation. Due to this they are also much larger than prokaryotes. The typical size of a prokaryotic cell is 0.1-10μm where a typical eukaryote measures 10-100μm which is a big difference in size (Toole & Toole,1995). The nucleus in eukaryotes contains the DNA which is the cells genetic material and is contained by the nuclear envelope. The DNA is linear and forms into chromosomes before cell division.
Prokaryotes are most always single-celled, except when they exist in colonies. These ancestral cells, reproduce by means of asexual reproduction, duplicating their genetic material and then essentially splitting to form two daughter cells identical to the parent.The most noticeable feature that differentiates these more complex cells from prokaryotes is the presence of a nucleus, a double membrane-bound control center separating the genetic material, DNA (deoxyribonucleic acid), from the rest of the cell. In addition to the plasma membrane,eukaryotic cells contain internal membrane-bound structures called organelles. Organelles, such as mitochondria and chloroplasts, are both believed to have evolved from prokaryotes that began living symbiotically within eukaryotic cells. These vital organelles are involved in metabolism and energy conversion within the cell.
During transcription, RNA polymerase makes a copy of a gene from the DNA to mRNA as needed. This process is similar in eukaryotes and prokaryotes. One notable difference, however, is that prokaryotic RNA polymerase associates with mRNA-processing enzymes during transcription so that processing can proceed quickly after the start of transcription. The short-lived, unprocessed or partially processed, product is termed pre-mRNA; once completely processed, it is termed mature mRNA. [edit] Eukaryotic pre-mRNA processingMain article: Post-transcriptional modification Processing of mRNA differs greatly among eukaryotes, bacteria, and archea.
This method to produce offspring with identical genes with that of the parent can be reffered to as reproductive cloning. A broader view of cloning includes the production of tissues and organs by increasing cell or tissue cultures through the use of stem cells. When an egg or ovum is fertilized and begins dividing, stem cells are all alike. As cells divide, some cells differentiate and become stem cells that produce specific tissues and then organs. This process is called therapeutic cloning.
Enzymes called topoisomerases produce breaks in the DNA molecules and then reconnect the strands, relieving strain and effectively preventing tangling and knotting during replication. DNA polymerase adds new nucleotides to a growing strand of DNA. Because DNA polymerase must adhere to an existing template, an RNA primer is first created at the site of replication. The RNA primer is synthesized by primase, an enzyme that is able to start a new strand of RNA opposite a DNA strand. After a few nucleotides have been added, the primase is displaced by DNA polymerase, which can then add subunits to the 3’ end of the short RNA primer.
The genetically modified plasmid is now inserted and introduces into a new organism which starts divides rapidly. Genetic engineering in humans has been becoming more common and is being used for different medical applications daily. Genetic engineering is for example used to increase the levels of insulin in the human body. To produce large amounts of ensiling, these cells are contained and reproduced in large fermentation vessels containing the needed nutrients for growth and development. The produced insulin is then purified and packaged to be used by many patients including diabetics.
The new viral RNA serves as blueprint. Other enzymes use it to produce proteins that will become new virus capsules. (5) An enzyme called protease cuts the long, unmilled proteins into shorter piece, which clip together to form new capsule. (6) The completed capsule bud from the surface of the cell. AIDS AS A CONCERN FOR