Meaning of DNA (deoxyribonucleic acid)

What is DNA (deoxyribonucleic acid):

DNA is the base macromolecule of heredity.It is a nucleic acid that contains the information of the hereditary characteristics of each living being and the sequences for the creation of amino acids that will generate the proteins vital for the functioning of organisms.

DNA or DNA (for its acronym in English) is an acronym for deoxyribonucleic acid and its main function is to store all the information necessary for the expression of certain characteristics, in segments called genes or packed into chromosomes.

In addition, the DNA transcribes the information of the amino acid sequences in the RNA or ribonucleic acid, so that these instructions can be protected from the nucleus to the ribosomes, which will translate the information to create the proteins (chains of amino acids).

With reference to the above, it can be seen that DNA is coding and RNA is not coding but they work together for the transmission of genetic information.

DNA began to be studied in 1868 by Friedrich Miescher, which he called nucleic acids together with RNA. The description of DNA was first published in 1953 by Jamen Watson and Francis Crick, both recipients of the 1962 Nobel Prize in Medicine.

DNA characteristics

The main characteristic of human DNA is its double helix structure, also known as helical.

Where is DNA located?

In prokaryotic cells (without a defined cell nucleus), DNA is found in the cytosol, along with the other elements that float in it. Thus. its replication is immediate, that is, it does not need to resort to other processes to transmit genetic information at the time of cell division.

In eukaryotic cells (with a defined cell nucleus), DNA is located in the cell nucleus. There are 2 ways in which DNA transmits genetic information within it:

Before cell division: it replicates and is packaged with other molecules and proteins forming a larger molecule called a chromosome. In this way, during mitosis, the 2 daughter cells will carry a copy of the original DNA.

For the translation or synthesis of proteins: the information of the sequences of 3 nitrogenous bases (codon) that will determine the functions of the DNA proteins of each organism need messenger ribonucleic acid (mRNA) to travel safely out of the nucleus, towards the ribosomes.

What are the functions of DNA?

DNA is characterized because it must fulfill 2 fundamental functions:

  1. Replication: must be able to replicate. In this sense, a DNA chain contains 2 strands of information that can be replicated in another 2 double chains.
  2. Expression: must be able to use information to express hereditary characteristics or to encode proteins for the proper functioning of the body.

DNA structure

DNA is a macromolecule with a double helix structure. The 2 strands that make up DNA go in the opposite direction, joined by their nitrogenous bases (Adenine, Guanine, Cytosine and Thymine). It is for this reason that the structure of DNA is often referred to as an inverted ladder.

What are the parts of DNA?

DNA is made up of deoxyribonucleotides, chains of nucleotides where each unit, in turn, is made up of 3 parts:

  1. a 5-carbon sugar molecule (deoxyribose for DNA and ribose for RNA),
  2. a phosphate group and,
  3. 4 nitrogenous bases (Adenine, Guanine, Cytosine and Thymine in DNA; Adenine, Guanine, Cytosine and Uracil for RNA).

Replication of DNA

DNA replication occurs before the cell divides and consists of obtaining identical copies of the fundamental cellular information for its transfer from one generation to another, thus constituting the basis of genetic inheritance.

The coiled DNA (chromosome) is untangled by the topoisonerase enzyme so that later, the helicase enzyme acts breaking the hydrogen bonds of the nitrogenous bases (Adenine, Guanine, Cytosine and Thymine) to separate the 2 strands.

Each strand has a directionality and each end is called 5 "and 3" (five prime and three prime), being that it is only possible to add nucleotides at the 3 "end, that is, the direction of elongation will always be from 5" to 3 ".

Taking this into account, the nucleotides that will be paired with the information of a strand will be added by the DNA polymerase in the direction 5 "to 3", where the hydrogenated Adenine bases always bind with the Thymine, the Thymine always with the Adenine, the Guanine always with the Cytosine and the Cytosines always with the Guanine.

DNA transcription

The nucleotide sequence established in a DNA strand is transcribed into a messenger RNA (mRNA). The transcription of DNA to the corresponding mRNA is similar to the process of DNA replication, in the sense of the association of the nitrogenous bases.

In this way, the hydrogenated Adenine bases join with the Uracil, the Thymine always continue to join the Adenine, the Guanine always with the Cytosine and the Cytosines always with the Guanine.

Once the transcription is finished, the corresponding mRNA will transport the information to the ribosomes to begin with the translation or protein synthesis.

DNA and RNA

DNA and RNA are nucleic acids and together they are responsible for maintaining, replicating, storing and transporting the genetic information that defines each living being. Thanks to this information, the unique characteristics d

DNA stands for deoxyribonucleic acid, it has a deoxyribose sugar and its nitrogen base is composed of: adenine, cytosine, guanine and thymine. It is characterized by having 2 strands wound together to form a double helix.

In turn, RNA, that is, ribonucleic acid, contains ribose sugar, its nitrogen base is made up of: adenine, cytosine, guanine and uracil. It is made up of a single strand.

However, both are nucleic acids composed of sugars, a phosphate group, and a nitrogen base.

DNA, chromosome and genes

DNA is the helical chain that contains the genetic information and for the protein synthesis of each organism. It is packed into chromosomes at the time of meiosis or cell division, a preparatory phase so that the daughter cells each have an exact copy of the original DNA.

Instead, a gene is a segment of the DNA chain that defines or expresses a certain inherited trait.

DNA types

Recombinant DNA

Recombinant or recombined DNA is a genetic recombination technology, that is, they identify genes (segments of DNA that express certain characteristics of an organism), combine them and create new sequences. That is why this technology is also called DNA in vitro.

See also Genetics.

Mitochondrial DNA

Mitochondrial DNA is a fragment of nucleic acid in mitochondria. The mitochondrial genetic material is inherited exclusively by the maternal part. Mitochondrial DNA was discovered by Margit M. K. Nass and Sylvan Nass using the electron microscope and a marker sensitive to mitochondrial DNA.

Mitochondria are small organelles inside eukaryotic cells, in order to produce energy for the cell to fulfill its functions. However, each mitochondrion has its own genome and cellular DNA molecule.

Tags:  Sayings And Proverbs General Expressions-Popular