DNA is the life code; it is responsible for the resemblance between parents and children, and for having a common template for individuals from the same species. It contains all the genetic information, the building receipt for every living organism, from the most simple to the most complex one
DNA (Deoxyribonucleic acid)
DNA is a molecule that encodes the genetic instructions used in the development and functioning of all known living organisms and many viruses.
Most of our DNA is in the nucleus of cells. Every cell in our body stores a copy of this information. Each DNA molecule consists of two strands of nucleotides which cross each other in a double helix. That is the typical image that comes to our mind when talking about DNA.
Nucleotides are actually smaller molecules, and there are four types: Adenine (A), Thymine (T), Cytosine (C) and Guanine (G). The four combine to form the genetic code.
When cells are divided they organize the genetic information in structures called chromosomes. Genomic DNA is tightly and orderly packed in structures called genes. The new copy should be identical, but sometimes it is not. Typically some mistakes may occur in the process, known as mutations. We all have some mutations in our genes and this is mostly what makes us different. Mutations sometimes provide an advantage over other individuals and contribute to the evolution of the species, despite sometimes they can cause disease or other negative consequences. However, mutations in most cases are not negative.
Human cells contain two sets of chromosomes, one inherited system of the mother and the other one from the father. The mother's egg cell contains half of the 46 (23) and the father's sperm carries half (23) of 46 chromosomes. Together, the baby has all 46 chromosomes. A gene is a unit of heredity and is a region of DNA that influences a particular characteristic in an organism; determine the development of a living being, the presence or absence of a physical feature, or a disease predisposition, if this latter one has a genetic origin.
Genetics (the study of genes and heritage) and genomics (study of genes, their interactions and the influence of the environment) are important to our body because the genome is the same in all cells in our body.
The cells from our skin, brain and heart are different, but it is the genome the one who explains this distinction. Each gene contains information for the production of a single protein which performs a specialized function in the cell. About 20,000 genes in the cell guide the growth, development and health of animals and humans. The genome, a set of genes of a human being, IS UNIQUE, except for identical twins.