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.
Helicases are enzymes that bind and may even remodel nucleic acid or nucleic acid protein complexes. There are DNA and RNA helicases. DNA helicases are essential during DNA replication because they separate double-stranded DNA into single strands allowing each strand to be copied.During DNA replication, DNA helicases unwind DNA at positions called origins where synthesis will be initiated.DNA helicase continues to unwind the DNA forming a structure called the replication fork, which is named for the forked appearance of the two strands of DNA as they are unzipped apart.here are DNA and RNA helicases. DNA helicases are essential during DNA replication because they separate double-stranded DNA into single strands allowing each strand to be copied. During DNA replication, DNA helicases unwind DNA at positions called origins where synthesis will be initiated.