Ad
related to: sequence meaning and examples biology
Search results
Results From The WOW.Com Content Network
A sequence in biology is the one-dimensional ordering of monomers, covalently linked within a biopolymer; it is also referred to as the primary structure of a biological macromolecule. While it can refer to many different molecules, the term sequence is most often used to refer to a DNA sequence or a protein sequence .
However, it is sometimes desirable to sequence RNA molecules. While sequencing DNA gives a genetic profile of an organism, sequencing RNA reflects only the sequences that are actively expressed in the cells. To sequence RNA, the usual method is first to reverse transcribe the RNA extracted from the sample to generate cDNA fragments. This can ...
DNA sequencing is the process of determining the nucleic acid sequence – the order of nucleotides in DNA.It includes any method or technology that is used to determine the order of the four bases: adenine, guanine, cytosine, and thymine.
The presence of repeated sequence DNA makes it easier for areas of homology to align, thereby controlling when and where recombination occurs. In addition to playing an important role in recombination, tandem repeats also play important structural roles in the genome. For example, telomeres are composed mainly of tandem TTAGGG repeats. [15]
Sequence homology is the biological homology between DNA, RNA, or protein sequences, defined in terms of shared ancestry in the evolutionary history of life. Two segments of DNA can have shared ancestry because of three phenomena: either a speciation event (orthologs), or a duplication event (paralogs), or else a horizontal (or lateral) gene ...
A regulatory sequence is a segment of a nucleic acid molecule which is capable of increasing or decreasing the expression of specific genes within an organism. Regulation of gene expression is an essential feature of all living organisms and viruses.
However, comparing these new sequences to those with known functions is a key way of understanding the biology of an organism from which the new sequence comes. Thus, sequence analysis can be used to assign function to coding and non-coding regions in a biological sequence usually by comparing sequences and studying similarities and differences.
Regulatory sequences are located at the extremities of genes. These sequence regions can either be next to the transcribed region (the promoter) or separated by many kilobases (enhancers and silencers). [8] The promoter is located at the 5' end of the gene and is composed of a core promoter sequence and a proximal promoter sequence.