FACTOID # 132: Of all the nations of the world, China has the most people. But there are 71 nations that are more crowded.
 
 Home   Encyclopedia   Statistics   Countries A-Z   Flags   Maps   Education   Forum   FAQ   About 
 
WHAT'S NEW
RECENT ARTICLES
More Recent Articles »
 

Encyclopedia > DNA sequence
part of a DNA sequence
Enlarge
part of a DNA sequence

A DNA sequence (sometimes genetic sequence) is a succession of letters representing the primary structure of a real or hypothetical DNA molecule or strand, The possible letters are A, C, G, and T, representing the four nucleotide subunits of a DNA strand (adenine, cytosine, guanine, thymine), and typically these are printed abutting one another without gaps, as in the sequence AAAGTCTGAC. This coded sequence is sometimes referred to as genetic information. A succession of any number of nucleotides greater than four is liable to be called a sequence. With regard to its biological function, which may depend on context, a sequence may be sense or anti-sense (see DNA), and either coding or noncoding. DNA sequences can also contain "junk DNA". Image File history File links Part of a DNA sequence Created by Chris Dixon File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Image File history File links Part of a DNA sequence Created by Chris Dixon File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... A protein primary structure is a chain of amino acids. ... Space-filling model of a section of DNA molecule Deoxyribonucleic acid (DNA)nucleic acid that contains the genetic instructions specifying the biological development of all cellular forms of life (and many viruses). ... A molecule is the smallest particle of a pure chemical substance that still retains its chemical composition and properties. ... A nucleotide is a monomer or the structural unit of nucleotide chains forming nucleic acids as RNA and DNA. A nucleotide consists of a heterocyclic nucleobase, a pentose sugar, and a phosphate or polyphosphate group. ... Adenine is one of the two purine nucleobases used in forming nucleotides of the nucleic acids DNA and RNA. In DNA, adenine (A) binds to thymine (T) via two hydrogen bonds to assist in stabilizing the nucleic acid structures. ... Cytosine is one of the 5 main nucleobases used in storing and transporting genetic information within a cell in the nucleic acids DNA and RNA. It is a pyrimidine derivative, with a heterocyclic aromatic ring and two substituents attached (an amine group at position 4 and a keto group at... Guanine is one of the four main nucleobases found in nucleic acids (, DNA and RNA). ... Thymine, also known as 5-methyluracil, is a pyrimidine nucleobase. ... Information is a word with many meanings depending on context, but is as a rule closely related to such concepts as meaning, knowledge, instruction, communication, representation, and mental stimulus. ... Space-filling model of a section of DNA molecule Deoxyribonucleic acid (DNA)nucleic acid that contains the genetic instructions specifying the biological development of all cellular forms of life (and many viruses). ... RNA codons. ... In genetics, noncoding DNA describes DNA which does not contain instructions for making proteins (or other cell products such as RNAs). ... In molecular biology, junk DNA is a collective label for the portions of the DNA sequence of a chromosome or a genome for which no function has been identified. ...


See also


  Results from FactBites:
 
Significantly Lower Entropy Estimates for Natural DNA Sequences (7298 words)
DNA may be imagined to be a highly ordered, purposeful molecule, and one might therefore reasonably expect statistical models of its string representation to produce much lower entropy estimates.
DNA may be imagined to be a highly ordered, purposeful molecule, and one might therefore reasonably expect statistical models of its string representation to produce much lower entropy estimates, and confirm our intuition that it is far from random.
The DNA sequences were chosen to pass the following criteria: sufficient length to support this type of entropy estimation method, inclusion of a wide variety of species and sequence types to evaluate the generality of the method, and inclusion of sequences used to benchmark other published methods.
Curved DNA in promoter sequences (6238 words)
Nair reported the presence of an intrinsic DNA bend with a broad locus of curvature for the human cdc2 promoter and concluded that this intrinsic bend might influence the protein-induced bending of a promoter region and therefore the subsequent interaction of regulatory factors with the transcription machinery [Nair, 1998].
Sequences of human exons and introns were taken from the Non-Redundant Functionally Equivalent Sequences Database (NRFES) of Konopka [Konopka, 1993].
Furthermore, recent studies on the sequence patterns in nucleosomal DNA indicates that only certain DNA sequences bind to the most stable nucleosome subset and that there is a significant amount of these sequences in centromeres suggesting a functional role for these stable nucleosomes [Widlund et al., 1997].
  More results at FactBites »

 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your location
Your comments
Please enter the 5-letter protection code


Lesson Plans | Student Area | Student FAQ | Reviews | Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms.