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Characteristics of DNA and RNA molecules and their function:

1.What unique ability do DNA molecules have? Why is this ability so important?
2.What are the similarities and differences in DNA and RNA?
3.What are the respective functions in general and in protein systhesis?
4.What are the various factors that might damage genes?
5.Explain the process of mitosis along with its various stages.

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1.DNA molecules are the most important stable molecules which remain concentrated in the nucleus, particularly in the chromosomes of all eukaryotes. They are nucleic acids which form the genetic material of most organisms. Extra nuclear DNA molecules are found to occur in the mitochondria and chloroplasts of higher organisms, while naked DNA molecules are found suspended in the cytoplasm of prokaryotes. It is considered as the master molecule of a biological system as it directs all the activities of a cell from the nucleus. DNA molecules have the unique ability of undergoing replication or self-duplication, thus each molecule is capable of making an identical copy of itself. This occurs prior to cell division resulting in the formation of two daughter molecules. The ability of replication or self-duplication of DNA molecules has an important role to play in order to maintain the genetic continuity of a species. Replication is essential for carrying the genetic information from generation to generation during the process of reproduction.

2.The similarities between DNA and RNA molecules are; both nucleic acids are made up of nucleotides which are a combination of a pentose sugar, nitrogen bases and a phosphate groups. They have a pentose sugar linked to a phosphate group at one end and a nitrogenous base at the other end. They are made up of a number of nucleotides, thus referred to as Polymers of nucleotides. Both of them are made up of two types of nitrogen bases namely purines and pyrimidines. Both DNA and RNA molecules comprise of four nitrogen bases, out of which three are similar namely, Adenine, Guanine, and Cytosine. DNA and a type of RNA known as genetic RNA which occurs among viruses, for instance human AIDS virus, are capable of replication or self-duplication and can undergo mutation and recombination, which are changes at the genetic level.

The differences between DNA and RNA molecules are; DNA is mainly confined to the chromosomes in the nucleus, while some DNA is also found in the mitochondria and chloroplasts. RNA is mainly confined to the cytoplasm, but it is also found in the nucleolus, nucleoplasm, and chromosomes. DNA is in the form of a double helix, which is spirally coiled, while RNA is single stranded. Deoxyribose is the sugar molecule in DNA, while ribose is the sugar molecule in RNA. The four nitrogen bases found in DNA are Adenine, Guanine, Cytosine, and ...

Solution Summary

The solution deals with the unique ability possessed by DNA molecules along with the explanation as to why the particular ability is very important. It deals with the similarities and differences that exist among DNA and RNA molecules, their respective functions in general and protein synthesis in particular. The factors that are responsible for damaging genes along with the process and various stages of mitosis have also been included.

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