Differences between DNA and RNA

We describe the characteristics and functions of DNA and RNA and clarify their differences.

All organisms have nucleic acids. They may not be so well known by this name, but if I say "DNA" it may change.

The genetic code is considered a universal language because it is used by all types of cells to store information about their functions and structures, which is why even viruses use it to survive.

In this article I will focus on clarifying the differences between DNA and RNA to understand them better.

What are DNA and RNA?

There are two types of nucleic acids: deoxyribonucleic acid deoxyribonucleic acid, abbreviated as DNA or DNA or DNA for short, and ribonucleic acid (RNA). These elements are used to make copies of cells, which will go on to build the tissues and organs of living beings in some cases, and unicellular life forms in others.

DNA and RNA are two very different polymers, both in structure and function; however, at the same time they are related and essential for the correct functioning of cells and bacteria. functioning of cells and bacteria.. Ultimately, although their "raw material" is different, their function is similar.

Nucleotides

Nucleic acids are formed by chains of chemical units called "nucleotides". called "nucleotides". In a manner of speaking, they are like the building blocks that make up the genotype of the various forms of life. I will not go into much detail about the chemical composition of these molecules, although therein lie several of the differences between DNA and RNA.

The centerpiece of this structure is a pentose (a 5-carbon molecule), which in the case of RNA is a ribose, while in DNA it is a deoxyribose. Both give their names to the respective nucleic acids. The deoxyribose gives more chemical stability than the ribose, making it safer to use than deoxyribose.and thus makes the structure of DNA more secure.

Nucleotides are the building block for nucleic acids, but they also play an important role as a free molecule in energy transfer in metabolic processes. energy transfer in the metabolic processes of cells (e.g. in of cells (e.g. in ATP).

Structures and types

There are several types of nucleotides and not all of them are found in both nucleic acids: adenosine, guanine, cytosine, thymine, and uracil.. The first three are shared in both nucleic acids. Thymine is only in DNA, while uracil is its counterpart in RNA.

The configuration that nucleic acids take is different depending on the form of life we are talking about. In the case of eukaryotic eukaryotic animal cells such as human cells differences are observed between DNA and RNA in their structure, in addition to the aforementioned different presence of the nucleotides thymine and uracil.

The differences between RNA and DNA

Below you can see the basic differences between these two types of nucleic acid.

1. DNA

Deoxyribonucleic acid is structured by two strands, which is why we say that it is double-stranded. These chains draw the famous linear double helix linear, because they intertwine with each other as if they were a braid. In turn, the DNA strands are coiled into chromosomes, entities that remain grouped together inside the cells.

The joining of the two DNA strands occurs through bonds between the opposing nucleotides. This is not done randomly, but each nucleotide has an affinity for one type and not for another: adenosine always binds to a thymine, while guanine binds to cytosine.

In human cells there is another type of DNA apart from nuclear DNA: mitochondrial DNA, the genetic material which is located inside the mitochondria, the organelle in charge of cellular respiration.

Mitochondrial DNA is double-stranded but its shape is circular rather than linear. This type of structure is typically observed in bacteria (prokaryotic cells), so it is thought that the origin of this organelle may have been a bacterium that joined eukaryotic cells.

2. RNA

Ribonucleic acid in human cells is found in linear form, but is single-stranded. but it is single-stranded, i.e. it is configured as a single strand. In addition, their strands are shorter than DNA strands when compared in size.

Nevertheless, there is a wide variety of RNA types, with three being the most prominent, as they share the important function of protein synthesis:

• Messenger RNA (mRNA)acts as an intermediary between DNA and protein synthesis.
• Transfer RNA (tRNA)transports the amino acids (protein-forming units) in protein synthesis. There are as many types of tRNA as amino acids used in proteins, namely 20.
• ribosomal RNA (rRNA)ribosomal RNA (rRNA): together with proteins, they form part of the structural complex called the ribosome, which is responsible for carrying out protein synthesis.

Duplication, transcription and translation

Those that give this section its name are three very different processes linked to nucleic acids, but simple to understand.

Duplication involves only DNA. It occurs during cell division, when the genetic content is replicated. As the name suggests, this is a duplication of duplication of genetic material to form two cells with the same content. with the same content. It is as if nature were making copies of the material that will later be used as a blueprint indicating how an element is to be constructed.

Transcription, on the other hand, affects both nucleic acids. In general, DNA needs a mediator to be able to "extract" the information from the genes and synthesize proteins; for this it makes use of RNA. Transcription is the process of transferring the genetic code from DNA to RNA, with the structural changes that this entails.

Translation, finally, acts only on RNA. The gene already contains the instructions on how to structure a particular protein and has been transcribed into RNA; now all that remains to be done is to from nucleic acid to protein.

The genetic code contains different combinations of nucleotides that have a meaning for protein synthesis. For example, the combination of the nucleotides adenine, uracil and guanine in RNA always indicates that the amino acid methionine will be placed. Translation is the step from nucleotides to amino acids, ie, what is translated is the genetic code..

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