| 释义 |
junk DNA
junk DNAa region of DNA that usually consists of a repeating DNA sequence, does not code for protein, and has no known functionjunk DNAn. A DNA sequence that is part of a genome and is not known to code for proteins or to regulate the expression of genes. Junk DNA may constitute up to 95 percent of the human genome and is postulated to be involved in the evolution of new genes and possibly the repair of genes.
[From junk.]junk DNA n (Genetics) DNA that consists of repeated sequences of nucleotide and has no apparent function junk DNA
n. segments of DNA that have no apparent genetic function. [1990–95] Thesaurus| Noun | 1.junk DNA - stretches of DNA that do not code for genes; "most of the genome consists of junk DNA"deoxyribonucleic acid, desoxyribonucleic acid, DNA - (biochemistry) a long linear polymer found in the nucleus of a cell and formed from nucleotides and shaped like a double helix; associated with the transmission of genetic information; "DNA is the king of molecules" |
Translationsjunk DNA
junk DNAthat portion of DNA that is not transcribed and expressed, comprising a major fraction of the base pairs of the human genome; much of this DNA is repetitive in seuqence and appears to serve no purpose; its function is not known. segments of DNA that appear to serve no function and are replicated along with the rest of the DNA that serves vital functions; examples are pseudogenes and tandemly repeated DNA sequences that seem functionless but are retained by unequal crossing-over. Synonym(s): selfish DNAjunk DNAn. A DNA sequence that is part of a genome and is not known to code for proteins or to regulate the expression of genes. Junk DNA may constitute up to 95 percent of the human genome and is postulated to be involved in the evolution of new genes and possibly the repair of genes.Any long stretch of non-protein-coding DNA that composes 97–98% of the human genome, which has been highly conserved in plant and animal genomes over millions of years. It is now recognised that non-coding DNA determines the differences in transcription rates of genes, which is what makes each of us unique, making junk DNA is a misnomerjunk DNA (jŭngk) The portion of DNA that is not transcribed and expressed, comprising about 90% of the 3 billion base pairs of the human genome; its function is not known.
Synonym(s): selfish DNA. junk DNA The long sequences of DNA between those segments that code for protein. Only three percent of DNA consist of functional genes. The rest is junk DNA and is preserved over millions of years of evolution. Species differ not so much in the number of active genes as in the amount of junk DNA. These facts suggest the junk DNA has an important function, not yet discovered.junk DNA DNA of no apparent function, generally in GENOMES ofEUKARYOTES, where sequences have been repeated. Also called non-coding DNA.junk DNA
Words related to junk DNAnoun stretches of DNA that do not code for genesRelated Words- deoxyribonucleic acid
- desoxyribonucleic acid
- DNA
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