Dna Structure Essay

Submitted By purplechik
Words: 515
Pages: 3

Title of Lab: DNA Models
Objective: To identify the parts and importances of the DNA structure
Questions:
The three parts of DNA is the phosphate, sugar, and bases.
The pieces that make up a nucleotide are a deoxyribose molecule, phosphate group, and a base.
There are four bases found in a DNA molecule, including Thymine, Adenine, Guanine, and Cytosine.
In base pairing, Thymine always pairs with Adenine and Guanine pairs with Cytosine. These bases in nucleotides together in specific sequences on a chromosome make differences in genes.
Thymine and Cytosine are pyrimidines. Pyrimidines are single-ringed organic base that will only attach to purines, which are Adenine and Guanine by hydrogen bond. Because Cytosine and Thymine are both pyrimidines, it cannot form a hydrogen bond with each other. Adenine shares two hydrogen bonds with Thymine, and Cytosine shares three hydrogen bonds with Guanine. If Adenine tried to bond with guanine, there would be an "incomplete bond," because one wants to make three hydrogen bonds and the other wants to make two.
The phosphate group in DNA acts as a binding agent.
The deoxyribose molecule acts as a backbone, stabilizing the DNA molecule.
The base pairing of the four bases, Thymine, Adenine, Guanine, and Cytosine, in specific sequences contain the genetic code.
The four bases never actually physically bond but connect through hydrogen bonds. The hydrogen bonds are why the two molecules of DNA can associate to form a double helix.
Conclusion:
The backbone of DNA is based on a repeated pattern of a sugar group or deoxyribose molecule and a phosphate group. Also the four complicated nitrogen bases, Cytosine, Thymine, Adenine, and Guanine. There are two classes of nitrogen bases called purines (double-ringed structures) and pyrimidines (single-ringed structures). The purines are Adenine and Guanine, and the pyrimidines are Cytosine and Thymine. Adenine always goes with Thymine, and Guanine always goes with Cytosine. The different strands