RM
Crossing over during meiosis, light micrograph
Light micrograph of crossing over between homologous stands of DNA (deoxyribonucleic acid) during metaphase I of meiosis (gamete formation). Here the crossing over is localised near to the centromere of each chromosome, where it's two sister chromatids are connected. During meiosis four daughter nuclei are formed from one parent nucleus after two stages of nuclear division. Meiosis occurs only in the sex cells (gametes) of the testes and ovaries. Crossing over is a natural genetic process that occurs between homologous chromosomes and leads to the switching of genetic material between the chromosomes. This recombination increases the genetic variation in a population. Silver stain., by DR. JUAN F. GIMENEZ-ABIAN / SCIENCE PHOTO LIBRARY
More
Top Categories