Rekombinatsioonitsükkel
Rekombinatsioonitsükkel is a biological process that occurs during meiosis, specifically within the prophase I stage. It refers to the exchange of genetic material between homologous chromosomes. Homologous chromosomes are pairs of chromosomes, one inherited from each parent, that carry genes for the same traits. During rekombinatsioonitsükkel, these homologous chromosomes align closely and then break at corresponding points. The broken segments are then exchanged and rejoined, effectively swapping genetic information. This exchange is facilitated by a protein structure called the synaptonemal complex. The resulting chromosomes are now recombinant, meaning they contain a mixture of alleles from both parental chromosomes. This process is crucial for genetic diversity. By creating new combinations of alleles, rekombinatsioonitsükkel increases the genetic variation within a population, which is essential for adaptation and evolution. Without rekombinatsioonitsükkel, offspring would inherit chromosomes that are identical to those of their parents, leading to a lack of genetic diversity. The points where the exchange of genetic material occurs are called chiasmata, which are visible under a microscope. The frequency of rekombinatsioonitsükkel can vary depending on the species and the specific chromosomal regions.