In This Article
In This Article
In cell biology, Ribonucleic acid (RNA) and Deoxyribonucleic acid (DNA) are considered the most important molecules. They are in charge of storing and reading genetic information that supports life.
RNA and DNA are linear polymers. They’re made up of bases, phosphates, and sugars. However, there are key differences between the two molecules. These dissimilarities enable RNA and DNA to work together while fulfilling their all-important roles.
Both DNA and RNA play important roles in biological functions.
There is a wide range of RNA functions — from the translation of genetic information to gene activity regulation for development, cellular differentiation, and changing environments.
DNA’s biological roles are vital for inheritance, protein-coding, and the provision of instruction for life and its many processes.
Here, we compare RNA vs. DNA, looking at their key differences in terms of function, location, structure, sugar content, bases, stability, and sensitivity to ultraviolet light.
|Ribonucleic Acid (RNA)||Deoxyribonucleic Acid (DNA)|
|It is responsible for the conversion of genetic information found inside DNA to a format used for protein-building. It is then moved to ribosomal protein factories.||It is responsible for replicating and storing genetic information. DNA is considered the blueprint for all of the genetic information found inside an organism.|
|Found in the ribosome, nucleus, and cytoplasm||Found in the nucleus, with small amounts in the mitochondria|
|Single-stranded molecule A-helix with shorter nucleotide chains||Double-stranded molecule B-helix with long-chain nucleotides|
|Adenine (A), Cytosine (C), Guanine (G), and Uracil (U)||Adenine (A), Cytosine (C), Guanine (G), and Thymine (T)|
|Unstable in alkaline conditions||More stable than RNA|
|Sensitivity to Ultraviolet (UV) Light|
|Relatively resistant to UV damage compared to DNA||Vulnerable to UV damage|
DNA, or Deoxyribonucleic acid, is the nucleic acid in cells which is the original blueprint for protein synthesis. DNA contains phosphates, deoxyribose sugar, and a unique sequence of the following nitrogenous bases: Adenine (A), Guanine (G), Cytosine (C), and Thymine (T).
DNA molecules hold the instructions needed by a living organism to develop, grow, and reproduce. Instructions are found inside every cell and are passed on from generation to generation.
DNA is composed of nucleotides containing a phosphate group, a nitrogenous group, and a sugar group. In determining the genetic code, the order of the nitrogenous bases Adenine (A), Guanine (G), Cytosine (C), and Thymine (T) is very important.
The human genome is composed of approximately 3 billion DNA base pairs.
The base pairing is as follows: Adenine and Thymine, Guanine and Cytosine.
DNA molecules appear as a spiral with two long strands. They are so long that they cannot fit inside the cell. To be able to do so, they are tightly coiled, producing chromosomes. Each chromosome has one DNA molecule. In humans, 23 pairs of chromosomes are present inside the cell’s nucleus.
Aside from storing genetic information as one of its primary functions, DNA also plays a part in:
RNA, or Ribonucleic acid, is the nucleic acid that plays a direct role in the synthesis of proteins. RNA is considered an important nucleotide found in all living cells, with long chains of nucleic acids. It acts as a “messenger,” forwarding instructions from DNA to control protein synthesis.
RNA molecules contain phosphates and sugar ribose. Just like DNA, it also has nitrogenous bases: Adenine (A), Guanine (G), Cytosine (C), and Uracil (U). Take note that in DNA, Uracil (U) is replaced by Thymine (T).
RNA plays three roles in protein synthesis: as a messenger, for transfer, and in ribosome production. These roles are reflected in the different types of RNA.
Not all of the genes in cells are expressed into Ribonucleic acid; only some of them are. The types of RNA are as follows:
Aside from these four, there are other types of RNA that continue to revolutionize molecular biology as we know it. These include siRNA (small interfering RNA) and miRNA (microRNA).
RNA and DNA are nearly identical nucleotide polymers. They have the same three base pairs, except for Thymine (T) and Uracil (U). Thymine is found in DNA, while Uracil substitutes Thymine in RNA.
RNA is found in the following sites: nucleus, cytoplasm, and ribosomes. Meanwhile, DNA is located in the mitochondria and nucleus of the cell.
While DNA is able to self-replicate, RNA cannot. RNA is synthesized into DNA as needed.
DNA is more stable because its deoxyribose sugar has one less oxygen-containing hydroxyl group. On the other hand, RNA has ribose sugar and is more reactive compared to DNA. Thus, DNA is considered a better genetic material than RNA.
Yes. RNA and DNA have three similar nitrogenous bases: Cytosine (C), Adenine (A), and Guanine. They also have phosphate backbones where the bases are attached.
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