DNA is deoxyribonucleic acid, a molecule made up of four nucleotides: adenine (A), thymine (T), cytosine (C), and guanine (G). DNA is present in all living organisms and is responsible for the transfer of hereditary characteristics. The double helix structure of DNA was discovered in 1953 by James Watson and Francis Crick.
DNA: what is it?
The genetic code is a sequence of nucleic acids which carries the information necessary for the production of proteins. DNA is a double helix formed by two strands wrapped around each other. The two strands are made up of sugars and phosphate. The amino acids form the side chains of the two strands and are linked together by hydrogen bonds.
Paragraph title: The function of DNA
Text: The main function of DNA is to store genetic information. It is present in all cells of the body and allows the reproduction and development of living organisms. DNA is also involved in the functioning of cells and organisms.
Paragraph title: The structure of DNA
Text: DNA is a double helix formed by two strands wrapped around each other. The two strands are made up of sugars and phosphate. The amino acids form the side chains of the two strands and are linked together by hydrogen bonds.
The function of DNA
DNA is a long molecule that contains the instructions needed to make all living organisms. The instructions are encoded in the structure of the DNA molecule itself.
DNA is therefore essential to life, because without it, no organism could exist. But how exactly does it work?
DNA consists of two strands wrapped around each other. These strands are made up of units called nucleotides. Each nucleotide is composed of a phosphate group, a deoxyribose (a type of sugar), and a nitrogen base.
There are four types of nitrogen bases: adenine, thymine, cytosine and uracil. The two strands of the same DNA are linked together by hydrogen bridges.
The sequence of nucleotides on the two strands of DNA is called DNA sequence. It is unique for each living organism.
The DNA double helix is very stable. This stability is necessary so that the instructions encoded in DNA are preserved over generations.
When cells multiply, the DNA duplicates so that each new cell has a complete copy of the DNA sequence.
DNA duplication is carried out by specialized enzymes. These enzymes “read” the DNA sequence and make a new complementary DNA molecule.
The double helix structure of DNA therefore allows its duplication, because enzymes can easily read the sequence of one strand to make another complementary one.
DNA is therefore essential to life because it allows the reproduction of living organisms.
The structure of DNA
The nucleus of each cell contains deoxyribonucleic acid (DNA), a helical molecule that stores the organism's genetic instructions. DNA is made up of two strands wrapped around each other, forming a double helix. DNA strands are made up of nucleic acid monomers called nucleotides. Each nucleotide is composed of a phosphate group, a sugar molecule (deoxyribose), and a nitrogen base. Nitrogen bases are the building blocks of DNA, and there are four different ones: adenine (A), thymine (T), cytosine (C), and guanine (G). The two strands of the same DNA are linked by hydrogen bridges between the complementary bases: A and T, and C and G. The four bases of DNA combine in a specific way to form codons, units of three nucleotides which codes for a particular amino acid. Codons are the basic units of protein synthesis.
DNA is a very important molecule because it determines the characteristics of living things. It is made up of two strands wrapped around each other, forming a double helix. DNA is very stable and can duplicate itself very precisely, allowing organisms to reproduce.