The Genetics is the branch of biology that is responsible for studying the mechanism of transmission of physical characteristics, biochemical or behavior from generation to generation. In other words, it studies the way in which each trait of individuals of the same species is transmitted or inherited. Genetics was born from the first plant crossing experiments conducted by the monk Gregor Mendel. Through his analyzes, he concluded that hereditary characteristics are determined by the presence of a couple of different hereditary factors, each one coming independently from one of the parents.
What is genetics
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The definition of genetics indicates that this is one that studies the characteristic features of living beings, whether they are physiological, morphological, behavioral, etc. which are transferred, generated and expressed from generation to generation, under various environmental circumstances. The concept of genetics also refers to what is associated with a beginning, beginning or the root of something.
Therefore, by fixing this link and determining that it is genetic, in a literal sense we can specify that it refers to everything that is relative to race or the birth of a being.
It is important to mention that in order to establish the etymological origin of the word genetic, it is necessary to move to Greek. Within this language the word genetic is formed from the unions of two words: "genos" which when translated means reason, origin or birth and the suffix "ikos" which means it is "relative to".
On the other hand, it is important to know what genes are, since these are the units of information that organisms use to transfer a trait to offspring. The gene has encoded the instructions to assimilate all the proteins of an organism. These proteins are the ones that will finally provide a place for all the characters of an individual (phenotype).
Each living being possesses for each particular trait, a pair of genes, one that it has received from its mother and the other from its father. There are genes that are dominant and always apply the information they carry. Others, unlike, are recessive and when this happens they only express themselves when there is an absence of the dominant genes. In other cases, the manifestation or not depends on the sex of the individual, at this point we speak of genes associated with sex.
Genes are actually fractions of deoxyribonucleic acid (DNA), a molecule that is located in the nucleus of all cells and makes up a fundamental part of chromosomes. In conclusion, DNA is a molecule in which the instructions that shape the development and functioning of living organisms are stored.
What does genetics study
As mentioned above, what genetics studies is heredity from a scientific perspective. Heredity is immanent to living organisms and therefore to human beings, its scope is so wide that it requires dividing it into several categories and subcategories that change according to the kind of species studied.
This science takes on a special importance when it studies the genetic inheritance of diseases, since in the same way that eye color is inherited from parents to children, there are also hereditary or genetic diseases. These conditions arise because the information to concentrate the proteins is not correct, it has been modified so that the protein is synthesized and cannot perform its function adequately, giving way to the group of symptoms of the disease.
"> Loading…Importance of the study of genetics
The importance of this discipline lies in the fact that thanks to it science has had the possibility of changing various abnormalities (genetic mutations) that arise in living beings due to the inheritance of their ancestors, which in certain cases, prevents them can live a normal life.
In the same way, it should be mentioned that thanks to what is genetics, many methods have been discovered that have served to control diseases that in previous years were fatal and that little by little their frequency has decreased.
His great contributions on the evolution of species and on the solutions to diseases or genetic problems have turned out to be his greatest advantage, even when in certain experiments they lead to controversies on a philosophical and ethical level.
History of genetics
The history of what is genetics is believed to begin with the investigations of the Augustinian monk Gregor Mendel. His study on hybridization in peas, presented in 1866, outlines what is later known as Mendel's laws.
In 1900 was the rediscovery of Mendel by Carl Correns, Hugo de Vries and Erich von Tschermak, and by the year 1915 the basic foundations of Mendelian genetics were implemented in a great variety of organisms, specialists developed the chromosome theory of inheritance, which was widely approved for the years 1925.
Simultaneously with the experimental works, the scientists created the statistical picture of the inheritance of populations, and passed its interpretation to the study of evolution.
With the basic models of genetic inheritance fixed, different biologists returned to studies on the physical characteristics of genes. In the 1940s and early 1950s, tests determined DNA as the fragment of chromosomes that possessed genes.
The vision of obtaining new model organisms, as well as bacteria and viruses, coupled with the discovery of the flimsy helix structure of DNA in 1953, established the transition to the age of molecular genetics. In subsequent years, some scientists developed methods for ordering both proteins and nucleic acids, while other experts worked out the relationship between these two classes of biomolecules, called the genetic code.
The regulation of gene expression became a major issue in the 1969s, and by the 1970s gene expression could be manipulated and controlled using engineering.
Mendel's laws
There are 3 laws stipulated by the scientist Mendel, which were established and used until today, these are:
Mendel's 1st law
Law of Uniformity of hybrids of the first filial generation:
This law establishes that if two pure species are linked for a certain character, the descendants of the first offspring will all be equal to each other, genotypically and phenotypically, and phenotypically identical to one of their parents (of dominant genotype), regardless of the direction of the link..
Represented with uppercase letters (A = Green) the dominant ones and in lowercase the recessive ones (a = yellow), it would be expressed in this way:
AA x aa = Aa, Aa, Aa, Aa.
In short, there are elements for each character which divide when the sex cells are created and join again when conception occurs.
Mendel's 2nd law
Principle of segregation:
The second law determines that in the second consanguineous generation achieved as a result of the crossing of two beings of the first consanguineous generation, the phenotype and genotype of the recessive subject of the first filial generation (aa) is rescued, obtaining 25%. The remaining 75%, phenotypically similar, 25% have a genotype of the other initial parental (AA) and the remaining 50% belong to the genotype of the first filial generation.
Mendel achieved this law by pairing different varieties of heterozygous organisms and managed to visualize through his tests that he achieved many with green skin features and others with yellow skin features, confirming that the balance was ¾ of green tone and 1/4 of yellow hue (3: 1)
Aa x Aa = AA, Aa, Aa, aa.
Mendel's 3rd law
Law of independent transfer or independence of characters.
In this law, Mendel concluded that different characteristics are inherited independently of each other, there is no relationship between them, therefore the genetic code of one trait does not harm the inheritance model of the other. It is only carried out in those genes that are not related (that is, that are found on different chromosomes) or that are located in very distant regions of the same chromosome.
In this case the offspring will continue the proportions interpreted with letters, of parents with two traits AALL and aall (where each letter symbolizes a trait and dominance by the lower or upper case), by between pairing of pure species, applied to two characteristics, as a result the following gametes would emerge: AL x al = AL, AL, aL, al.
"> Loading…Types of genetics
There are different types of gene transmission that are subject to discrete units called "genes." Human beings have 23 pairs of chromosomes, one pair coming from the father, and another pair from the mother. Chromosomes are structures that enclose genders and where there can be different forms of the same gene, which are called "alleles."
The types of inheritance are as follows:
Dominant-recessive
It happens when one of the genes dominates over another and their characteristics are dominant.
Incomplete dominant
It originates when neither of the pairs of genes dominates the other, so the inheritance characteristic is a combination of two alleles.
Polygenetics
It happens when an individual trait is handled by two or more alleles and there are minimal differences in its shape. For example, size.
Linked to sex
It happens when the alleles are found on the sex chromosomes (belonging to pair number 23), which are expressed by the letters "XY" in the male and "XX" in the female. Males can only transmit their Y chromosome to their male children, so no X-associated traits are inherited from the father. On the contrary, it happens with the mother who only transmits her X chromosome to her female daughters.
genetic engineering
Genetic engineering is a branch of engineering that, like all the others, are related to each other, since its main base is empirical and scientific knowledge that is applied for the effective conversion of the forces of nature and materials. in practical work for humanity, among other things.
Genetic engineering is the process that performs the alteration of the hereditary traits of a living being in a predetermined aspect by genetic mutations. They are usually applied to achieve that certain microorganisms such as viruses or bacteria, increase the synthesis of compounds, reproduce new compounds, or couple to different environments. Other uses of this method, also called the recombinant DNA method, comprise gene therapy, the delivery of a fused gene to an individual suffering from a malformation or suffering from diseases such as cancer or acquired immunodeficiency syndrome (AIDS).
Genetic engineering or also called genetic manipulation has developed a variety of techniques, but it has been duplication or cloning that has aroused the greatest controversy, as is the case with the cloning of the sheep "Dolly" in 1997. In addition, thanks to this In science, it has been possible to modify different anomalies that the living being presents due to the inheritance of its ancestors, to study and achieve the sequencing of the human genome, and to invent and discover methods to control diseases that were previously deadly.
"> Loading…About genetically modified organisms
Genetically modified organisms can be defined as living beings in which the genetic material DNA was artificially modified. This method is generally called "modern biotechnology", in other cases it is also called "recombinant DNA technology". This genetic variability allows the transfer of selected individual genera from one living being to another, as well as between unrelated species.
These techniques are used to create genetically modified organisms, which were later used to develop food crops that have been genetically modified.
