Each person normally has one pair of sex chromosomes in each cell. Females have two X chromosomes, while males have one X and one Y chromosome. Early in embryonic development in females, one of the two X chromosomes is randomly and permanently inactivated in cells other than egg cells.
Lesson Summary. You should now understand that DNA helicase has a very important job to do. It is responsible for opening up our DNA to allow for replication as well as transcription of our DNA. A DNA helicase is an enzyme that functions by melting the hydrogen bonds that hold the DNA into the double helix structure.hat is, until they meet DNA helicase. In order for DNA polymerase (in replication) or RNA polymerase (in transcription) to see the nucleotide bases that are to be used as a template, these hydrogen bonds must be broken to expose the much-needed the nucleotide bases.
Helicase separates the DNA into two template strands. RNA primase then adds a short sequence of RNA to the template strands. This short sequence of RNA is a primer which allows DNA polymerase III to bind to the strands and start the replication process.Once this is done, DNA polymerase III adds nucleotides to each template strand in a 5'â3' direction.his short sequence of RNA is a primer which allows DNA polymerase III to bind to the strands and start the replication process. Once this is done, DNA polymerase III adds nucleotides to each template strand in a 5'â3' direction.