Describe the chemical structure and function of DNA
DNA is a fundamental molecule responsible for the growth and maintenance of the human body. Since the discovery of DNA and its double helix structure though the Watson-Crick Model, there has been a significant increase in the understanding of human disease and development of effective treatment. DNA’s specific chemical structure allows it to carry out its function which therefore maintains our survival.
Deoxyribonucleic acid is a macromolecule consisting of double stranded polynucleotide chains joined together by hydrogen bonds between complimentary bases, forming the double helix. Each strand is made up of many nucleotides joined together in a complimentary fashion by phosphodiester bonds, …show more content…
Adenine and Guanine are Purines as they have a double ring structure whereas Cytosine and Thymine are Pyrimidines as they have a single ring structure. These bases, attached to the sugar-phosphate back bone of both strands, join adjacently in a complimentary fashion. This means that a purine will bind to a pyrimidine therefore Adenine always binds with Thymine, which forms two hydrogen bonds, and Guanine always binds with Cytosine, which forms three hydrogen bonds. This is known as complimentary base pairing and this enables the base pairs to be packed in the energetically most favourable arrangement in the double helix. This is because each base pair is of similar width causing the two sugar-phosphate backbones to be at a constant distance apart, allowing them to wind around each other to form a double helix, with one complete turn every 10 bases. These double helix DNA strands are then densely compacted into chromosomes to fit into the nucleus.
As well as storing genetic material and information in the nuclei, DNA has many different functions. One of DNA’s main functions is DNA replication, where DNA is copied in order to form two daughter cells of DNA. During DNA replication, DNA helicase causes the hydrogen bonds between the complimentary base pairs to break and the double helix to unwind into two strands. DNA polymerase then attaches to the start of each strand, acting as a template strand, for free RNA nucleotides to bind to the complimentary bases until the stop codon is reached, forming two daughter
DNA is a fundamental molecule responsible for the growth and maintenance of the human body. Since the discovery of DNA and its double helix structure though the Watson-Crick Model, there has been a significant increase in the understanding of human disease and development of effective treatment. DNA’s specific chemical structure allows it to carry out its function which therefore maintains our survival.
Deoxyribonucleic acid is a macromolecule consisting of double stranded polynucleotide chains joined together by hydrogen bonds between complimentary bases, forming the double helix. Each strand is made up of many nucleotides joined together in a complimentary fashion by phosphodiester bonds, …show more content…
Adenine and Guanine are Purines as they have a double ring structure whereas Cytosine and Thymine are Pyrimidines as they have a single ring structure. These bases, attached to the sugar-phosphate back bone of both strands, join adjacently in a complimentary fashion. This means that a purine will bind to a pyrimidine therefore Adenine always binds with Thymine, which forms two hydrogen bonds, and Guanine always binds with Cytosine, which forms three hydrogen bonds. This is known as complimentary base pairing and this enables the base pairs to be packed in the energetically most favourable arrangement in the double helix. This is because each base pair is of similar width causing the two sugar-phosphate backbones to be at a constant distance apart, allowing them to wind around each other to form a double helix, with one complete turn every 10 bases. These double helix DNA strands are then densely compacted into chromosomes to fit into the nucleus.
As well as storing genetic material and information in the nuclei, DNA has many different functions. One of DNA’s main functions is DNA replication, where DNA is copied in order to form two daughter cells of DNA. During DNA replication, DNA helicase causes the hydrogen bonds between the complimentary base pairs to break and the double helix to unwind into two strands. DNA polymerase then attaches to the start of each strand, acting as a template strand, for free RNA nucleotides to bind to the complimentary bases until the stop codon is reached, forming two daughter