Noncoding regions of DNA that have no apparent function. The
term "junk DNA" is a disparaging one, expressing some of the disappointment felt
by geneticists when they first gazed upon sizable segments of the genetic code and,
instead of seeing one wonderful gene after another, they saw a few exons surrounded
by vast stretches of "junk DNA."
E xons are the regions of DNA that contain the code for producing the polypeptide
molecules that make up protein. Each exon codes for a specific portion of the complete
protein. In humans and some other species, the exons are separated by long regions
of junk DNA.
However, junk DNA has been found to be even more conserved than protein-coding
regions of the DNA in humans and other mammalian species. The extent of conservation
indicates that there is some function for junk DNA that remains to be determined.
Junk DNA may prove not to be junk.
medical
dictionary, online medical dictionary, medical
terminology dictionary, free online medical
dictionary, medical dictionary, online medical
dictionary, medical terminology dictionary, free
online medical dictionary, dictionary medical,
dictionary medical online, dictionary medical
terminology, dictionary free medical online,
dictionary free medical, dictionary medical
terms, dictionary drug medical medicine,
dictionary health illustrated medical nursing
profession stedmans, dictionary English medical,
dictionary medical online terminology,
dictionary encyclopedia medical online,
condition dictionary medical, dictionary
medical, dictionary drug medical, medical
dictionary software, cyclopedic dictionary index
medical tabers thumb, medical dictionary, online
medical dictionary, medical terminology
dictionary
