In the studies off men protenor (squash bug), Elizabeth.B. Wilson turned out the necessity of X-chromosome during the gender commitment. The guy discovered that people out of Protenor have 14 chromosomes, when you find yourself boys have only thirteen chromosomes. In females, seven bivalents was formed and all the eggs discovered a haploid selection of chromosomes. When you look at the people, 6 bivalents and one unpaired chromosome (univalent) had been formed.
On anaphase I, this new unusual chromosome separated and each rod obtained eight chromosomes. At next meiotic section, the newest unpaired chromosome passed to at least one of these two girl cells. Thus 2 kinds of spermatozoa was basically shaped within the equivalent numbers, 50% which have six chromosomes and fifty% having seven chromosomes.
Fertilization of egg (eight chromosomes) because of the a sperm which have eight chromosomes lead a lady insect with fourteen chromosomes, while you are fertilization of your eggs which have a semen affect 6 chromosomes provides a male (with 13 chromosomes). When you look at the bacteria that have male heterogamety, the new intercourse chromosome limited to a man intercourse was called Y chromosome of the Wilson during the 1909.
R.C. Punnet and you may W. Bateson claimed the initial matter-of linkage. The phrase family genes is actually created because of the Bateson contained in this season.
Frans Alfons Janssens (1863-1924) state-of-the-art brand new Partial chiasma-sort of theory out-of crossing over. Continue Reading Montgomery tasked the term autosomes into chromosomes which are equivalent within the male and female, or any other than just sex chromosomes