Chromosome organization becomes clearer from a series of biochemical, electron microscopic скачать в хорошем качестве

Chromosome organization becomes clearer from a series of biochemical, electron microscopic

Chromosome organization becomes clearer from a series of biochemical, electron microscopic and X-ray crystallographic studies. When interphase chromatin is isolated in low salt buffer and observed under EM, 11 nm bead on string organization is seen. Interphase chromatin directly observed under EM shows 30 nm fibre. When histones are depleted from metaphase chromosome and visualized under EM, it shows a huge number of very large loops associated with scaffold. Following interpretations can be made from these: (JUNE 2014) A.11 nm fibre is formed when nucleosomes are brought closer by scaffold. B.30 nm interphase chromatin is formed by zig-zag organization of nucleosomes of 11 nm fibre. C.30 nm fibre makes a solenoid packing to form the metaphase chromosome. D.30 nm fibre gets organized into loops due to SARs getting associated with scaffold proteins and coming closer. The correct combination of interpretations is: (1)A and D (2) A and C (3)A and B (4) B and D