DNA Replication

DNA is a structure of double stranded nucleic acids, called a double helix. Nucleic acids are made up of several nucleotides put together. Nucleotides are made up of 3 parts : deoxyribose sugar, phosphate, and nitrogen base. DNA in the form of a double helix looks like a twisted ladder. DNA that is found in the nucleus of eukaryotic cells is called chromosomes.

Cells divide for an organism to grow or reproduce; every new cell needs a copy of the DNA or instructions to know how to be a cell. DNA replicates in the nucleus right before a cell divides. When it makes a copy, one half of the old strand is always kept in the new strand. DNA replication is the key for organisms to grow or reproduce.

The Process of DNA Replication

The process of replication begins as the double helix strand of DNA unwinds. The DNA now looks like a regular ladder. After this occurs the unwound DNA separates. An enzyme called helicase breaks the hydrogen bonds connecting the base pairs( A-T & C-G) to separate the DNA strands. Now there are two single-stranded nucleic acids.

The final step of replication is new nucleotides connect to the original strands. These new nucleotides are bound to the original ones with DNA polymerase. The final result is two identical double-stranded DNA molecules that contain an original strand and a new strand.

DNA Replication

Replication copies the genetic information.

According to the rules of base pairing, A pairs with T and C pairs with G. If the base sequence of one strand of DNA is known, the sequence of the other strand is also known. One strand can act as a template, or pattern, for another strand. During the process of DNA replication, a cell uses both strands of DNA as templates to make a copy of the DNA.

Each of your body cells contains 46 chromosomes made up of DNA. The DNA is copied each time of your cells needs to reproduce and divide into two new cells.

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Proteins carry out the process of replication.

DNA does not copy itself. Enzymes and other proteins do the actual work of replication. Here we will look at the process of replication in eukaryotes. The process is similar in prokaryotes.

First, some the enzyme Helicase pulls apart, or unzips, the double helix to separate the two strands of DNA. Other proteins keep the strands apart while the strands serve as templates. There are nucleotides floating around the nucleus. These nucleotides can pair up, according to the base pairing rules, with the nucleotides on the open strands. A group of enzymes called DNA polymerases bond the new nucleotides together. When the process is finished, there are two complete molecules of DNA, each exactly like the original double strand.