Barr (1908-) plus Bertram discover sex chromatin during the interphase nucleus off human females
The new sex chromatin is absent in the guys
He named the three genomes as A, B and D genomes. The genome studies involves crossing anywhere between polyploids and you will diploids and you can training the fresh chromosome combining through the meiosis on hybrids.
Emil Heitz demonstrated a link between amount of nucleoli in the interphase to the quantity of types of particular chromosomes (nucleolar chromosomes). Curt Tight, playing with translocations between the X and you can Y chromosomes showed new facts you to hereditary crossing-over is followed by a move away from parts ranging from homologous chromosomes.
H.B. Creighton and you will B. McClintock displayed into the maize one to hereditary recombination was with a reciprocal exchange of chromatin issue among them homologous chromosomes and ergo presented a good cytological proof crossing over.
(iv) Throughout synthesis off inter-chromomeric nations, the fresh associations can be found involving the chromomere of 1 chromosome and the chromomere of its homologue.
Ernst August Friedrich Ruska and you may Knoll authored the latest dysfunction from electron microscope and therefore contained an electron supply as well as 2 magnifier contacts. (περισσότερα…)