The following points highlight the top two models of chromosomes. The models are: 1. Multiple Strand Models 2. Single Strand Models. Model # 1. Multiple Strand Models: a) Simple Multi-Stranded Model: According to this model the chromosome consists of 64 double helices of DNA arranged in a parallel number, and twisted together like the strands of a rope. The difficulty [...]
In this article we will discuss about the six basic rules for DNA replication. The rules are: 1. Replication is a Semi-conservative Process 2. Replication has Direction 3. Replication Starts off a Unique Point on Bacterial and Viral Chromosomes 4. Replication of Both Strands Proceeds by the Addition of Nucleotide Monomers in the 5'-3' Direction and Others. Rule # 1. [...]
In this article we will discuss about the mechanisms of regulation of transcription in higher eukaryotes. In E. coli, the RNA polymerase holoenzyme (with sigma factor) contains all the information needed to accurately initiate transcription given proper promoter signals (-35 recognition sequence plus -10 Pribnow box). However, RNA polymerase II of eukaryotes, which transcribes most of the protein- encoding nuclear [...]