Introns are non-translated sections of a gene, i.e. they are not made into protein. The gene is stored in the chromosomes as DNA. When the corresponding protein is needed, the DNA is copied (transcribed) by RNA polymerase making a complementary copy of the gene made of RNA. This is then processed to remove the introns (the non-coding parts of the gene). It was long thought these introns hasdno use. However, there is evidence that they have a role in the processing of the RNA. In addition, introns allow more than one protein to be produced from a single gene. The RNA with the introns removed is now the messenger RNA (mRNA) which is transported out of the nucleus into the cytoplasm, where it is read by the ribosome, which produces the coded protein. See http://en.wikipedia.org/wiki/Intron
Introns are non-coding regions of the gene that do not contain instructions for making proteins. Removing introns allows only the exons, which contain coding instructions, to be translated into proteins. This process is known as RNA splicing and is essential for proper gene expression in eukaryotic cells.
Introns are non-coding sequences in DNA that are removed during RNA splicing, while exons are the coding sequences that are joined together to form the final mRNA transcript. RNA splicing is the process by which introns are removed and exons are joined together to produce a mature mRNA that can be translated into a protein.
Eukaryotic genes have regions called "introns" and "exons". Exons code for polypeptides (often specific domains or motifs), while introns don't code for anything (that we know of) and are removed. mRNA splicing is the process where an mRNA molecule is cut up (usually by the "spliceosome") to remove the introns from an mRNA message. This is advantageous for us eukaryotes because we can recombine exons in different orders, and even combine exons from different genes to generate many proteins from a smaller number of genes.
Exon DNA encodes for the RNA included in the final mRNA transcript that encodes for proteins. Intron DNA is found within exons, but is spliced out as the mRNA molecule is processed.
Eukaryotic genes contain all the information required to make the all proteins that all the cells in the organism will need. However, mRNA in cells only copies the region of DNA (gene) that is necessary for that cell. Hence, selectively copying DNA, leaving out junk DNA, the introns, and only copying necessary regions of the DNA, the exons. Further explanation: In DNA, there are many genes (segments of DNA). Some of these genes may be useful while others may not be useful. For example, for a cell found in the mouth, the gene that codes for insulin is not necessary, but the gene that codes for amylase is necessary. As the DNA in all of our cells are the same, this results in unnecessary genes known as introns. These introns will not be copied by the mRNA. Only the exons (necessary genes) will be copied. Thus resulting in a shorter mRNA as compared to DNA.
Prokaryotes have a single circular chromosome, wherease eukaryotes have many bar shaped chromsomes. Also, prokaryotes are single cell organisms (there are some single cell eukaryotes, but never multicellular prokaryotes). Because multicellular organisms have so many cells, (such as humans), their chromsomes have to contain a lot of information to provide details to the cell so it can carry out it's job. In eukaryotic cell DNA there are introns and exons. When a gene is needed to be expressed, the cell must remove the information in the sequence that is not needed; ie, the introns. It is believed that the same DNA sequence can actually code for more than one gene because of the cells ability to remove introns and keep exons. for example, the word 'strawberry' contains the code for three words: straw, berry, strawberry. by removing peices of the word, you are left with information that provides a different set of instructions. Prokaryotes do not have introns and exons.
Eukaryotic genes have regions called "introns" and "exons". Exons code for polypeptides (often specific domains or motifs), while introns don't code for anything (that we know of) and are removed. mRNA splicing is the process where an mRNA molecule is cut up (usually by the "spliceosome") to remove the introns from an mRNA message. This is advantageous for us eukaryotes because we can recombine exons in different orders, and even combine exons from different genes to generate many proteins from a smaller number of genes.
Eukaryotic genes have regions called "introns" and "exons". Exons code for polypeptides (often specific domains or motifs), while introns don't code for anything (that we know of) and are removed. mRNA splicing is the process where an mRNA molecule is cut up (usually by the "spliceosome") to remove the introns from an mRNA message. This is advantageous for us eukaryotes because we can recombine exons in different orders, and even combine exons from different genes to generate many proteins from a smaller number of genes.
Exons are the DNA sequences that code for proteins. Introns are involved however they dont carry the genetic information that exons carry, the variation provides for revolutionary flexibility allowing cells to shuffle exons between genes to make new ones. A great way to remember which is which is Exons (sounds like Executives, like in a business) have the information and introns (sounds like the interns of a business) dont know anything; exons and inrons, executives and interns. Easy huh?
Exons are part of both prokaryotic and eukaryotic. Introns are rarely present in the domain bacteria (common bacteria) while introns are present in some genes in domain archaea ("ancient" bacteria). Both are considered prokaryotic. No, they are only present on tRNA and rRNA.
Introns, exons
No, exons are the portions of DNA molecules that code for proteins. They are expressed through a process called transcription and translation to produce functional proteins in the cell.
Exon DNA encodes for the RNA included in the final mRNA transcript that encodes for proteins. Intron DNA is found within exons, but is spliced out as the mRNA molecule is processed.
Plato users, C. Introns, exons
During chromosome formation, genetic recombination occurs which results in one portion of the sister chromatids to be switched with another in order to increase variety. Also during DNA Replication the introns & exons are forced to reorganize with the introns removed for they are non-coding sequences of DNA. This allows more proteins to be created from less DNA while simultaneously increasing variety in an organism.
mRNA (messenger ribonucleic acid) contains the genetic information encoded in DNA. It serves as a template for protein synthesis by carrying this genetic information from the nucleus to the ribosomes in the cytoplasm.
Eukaryotic genes contain all the information required to make the all proteins that all the cells in the organism will need. However, mRNA in cells only copies the region of DNA (gene) that is necessary for that cell. Hence, selectively copying DNA, leaving out junk DNA, the introns, and only copying necessary regions of the DNA, the exons. Further explanation: In DNA, there are many genes (segments of DNA). Some of these genes may be useful while others may not be useful. For example, for a cell found in the mouth, the gene that codes for insulin is not necessary, but the gene that codes for amylase is necessary. As the DNA in all of our cells are the same, this results in unnecessary genes known as introns. These introns will not be copied by the mRNA. Only the exons (necessary genes) will be copied. Thus resulting in a shorter mRNA as compared to DNA.
Splicing is a cellular process where the DNA sequence is 'edited' before RNA is synthesised from it. This means that one DNA sequence can create different proteins. Sections that are spliced out are called introns, while exons are the sequences that remain. Prokaryotic organisms do not splice their genes, the DNA is copied directly to RNA. Since many biotechnological procedures use bacteria (prokaryotes) to test eukaryotic genes, the sequence needs to be 'spliced' before it can be expressed correctly by the bacterium. To do this researchers isolate the RNA (which lacks the introns) and convert it back to DNA, using reverse transcriptase. They then use this cDNA (complementary DNA) to express in the bacterial system. This is effectively recombinant DNA, because it does not occur naturally in the source organism.