Why is DNA repair important and major mechanisms of DNA repair?
The repair of damage to both DNA strands is particularly important in maintaining genomic integrity. There are two main mechanisms for repairing double strand breaks: homologous recombination and classical nonhomologous end joining. These mechanisms are mutagenic and can lead to a loss in genetic information.
What is the difference between DNA and RNA?
There are two differences that distinguish DNA from RNA: (a) RNA contains the sugar ribose, while DNA contains the slightly different sugar deoxyribose (a type of ribose that lacks one oxygen atom), and (b) RNA has the nucleobase uracil while DNA contains thymine.
What is the difference between the 5 and 3 end of DNA?
Atoms in each DNA nucleotide can be identified by specific numbers. One end of the chain carries a free phosphate group attached to the 5′-carbon atom; this is called the 5′ end of the molecule. The other end has a free hydroxyl (-OH) group at the 3′-carbon and is called the 3′ end of the molecule.
What does it mean to synthesize DNA?
DNA synthesis is the biological process by which a deoxyribonucleic acid (DNA) molecule is created. In the cell, each of the two strands of the DNA molecule acts as a template for the synthesis of a complementary strand.
What happens during DNA synthesis?
Abstract. DNA biosynthesis occurs when a cell divides, in a process called replication. It involves separation of the DNA double helix and subsequent synthesis of complementary DNA strand, using the parent DNA chain as a template.
What is the most common method of DNA synthesis?
Figure 2. Phosphoramidite-based synthesis of oligonucleotides. This synthesis process is the most commonly used for the synthesis of DNA oligonucleotides for gene synthesis. Figure 3.
Where does DNA synthesis occur?
(a) DNA synthesis starts at a specific place on a chromosome called an origin. In the first mechanism one daughter strand is initiated at an origin on one parental strand and the second is initiated at another origin on the opposite parental strand. Thus only one strand grows from each origin.
What are the advantages of DNA replicating exactly?
Each individual eukaryotic cell needs it’s own “copy” of genetic material, in order to synthesise the proteins involved in basic cell structure and function. So the “advantage” of DNA replication is the ability to preserve the full original sequence of base pairs in every cell.