Encyclopedia > Crossing over

  Article Content

Crossover

Redirected from Crossing over

Crossover is the process by which two chromosomes paired up during prophase I[?] of meiosis exchange a distal portion of their DNA. Crossover occurs when two chromosomes, normally two homologous instances of the same chromosome, break and connect to each other's ends. If they break at the same locus, this merely results in an exchange of genes. This is the normal way in which crossover occurs. If they break at different loci, the result is a duplication of genes on one chromosome and a deletion on the other. If they break on opposite sides of the centromere, this results in one chromosome being lost during cell division.

Any pair of homologous chromosomes may be expected to cross over three or four times during meiosis. This aids evolution by increasing independent assortment[?], and reducing the genetic linkage[?] between genes on the same chromosome.


For audio crossovers see electronic filters.



All Wikipedia text is available under the terms of the GNU Free Documentation License

 
  Search Encyclopedia

Search over one million articles, find something about almost anything!
 
 
  
  Featured Article
Canadian Music Hall of Fame

... Young 1983 Glenn Gould 1986 Gordon Lightfoot 1987 The Guess Who[?] 1989 The Band 1990 Maureen Forrester[?] 1991 Leonard Cohen 1992 Ian and Sylvia[?] 1993 ...

 
 
 
This page was created in 22.3 ms