This is a summary based on a aspect of DNA. The information gathered was taken from the article called "DNA Replication located at http://www.eurekascience.com/ICanDoThat/dna_rep.htm written by the Eureka Science Organization.
The article describes DNA replication by comparing it to a zipper. It says that "making a new chromosome is like making a new zipper by using the old zipper as a model." However, a zipper has only one kind of tooth, as stated in the article, but a chromosome has four, A, T, C, and, G. The article explains the unwinding process of the chromosomes by comparing it to the unwinding of the zipper. "The first thing the DNA replication team does is unwind (un-zip) a small section of the old chromosome and pull the two strands apart." .
This process of replication is discussed in chapter 3 of the text "Essentials of Physical Anthropology." The article just like the book shows a diagram of how "the bases which are exposed when unwind, attract unattached DNA nucleotides." This process as stated by the article helps to make exact copies of DNA, where A joins with T and C joins with G and T joins with A and G joins with C. "Because they fit together only in these pairs, the free nucleotides float in and line up in the proper order all by themselves" The nucleotides match up with a big one opposite a small one. Like the book states, "the previously joined parental nucleotide chains serve as models for the formation of new strands of nucleotides and as each stand is formed, its bases are joined to the bases of an original strand." When all this is done there are now two chromosomes. The new DNA strands are now exact copies of the old ones. It is very important for the copies to be exact because like the article says," otherwise we may have our noses coming out where our ear is located.
The site is very useful for giving in formation on DNA replication. The information is put forward in a simple form for easy understanding, especially when discussed as it pertains to the information on DNA in chapter 3.
