In this article we will discuss about:- 1. Coiled DNA Model 2. Nucleosome-Solenoid Model of Chromatin Fibres. Coiled DNA Model: This model of chromatin structure was proposed by DuPraw in 1965. As per this model, DNA molecule is associated with three classes of proteins: (i) Lysine rich histories: They are common to both A and B type fibres and are [...]
In this article we will discuss about the cell division and cell cycle in prokaryotes. Bacterial cell division is also termed as fission. The bacterial chromosome is circular and attached to the plasma membrane at a specific point. Its replication starts from an initiation point. Both the copies of the chromosome are attached to the plasma membrane, close to each [...]
In this article we will discuss about the chromosome movement during cell division. The chromosome movement during cell division is chiefly due to the spindle apparatus. This apparatus contains three different types of microtubules: (a) Astral microtubules, radiating from centrioles (found in animal cells only); (b) Continuous or inter-polar microtubules, passing from one pole to the other, account for the [...]