Polynucleotides
DNA molecules are very long but are packed into compact structures called chromosomes chromosome: One of the rod shaped bodies found in the nucleus of cells that contain genetic information (DNA). . Each DNA molecule consists of two twisted strands of bases that form a shape called a double helix. The two strands are held together by hydrogen bonds between pairs of bases. When a cell grows and divides into two, it first has to make a duplicate copy of each DNA molecule. If A occurs in one strand of a DNA molecule it will form a bond with T in the other strand. C and G will also only bond with each other. In this way it's possible to predict the order of bases on the other strand if the bases on one strand are known. The double helix describes the appearance of double-stranded DNA, which is composed of two linear strands that run opposite to each other, or anti-parallel, and twist together. Each DNA strand within the double helix is a long, linear molecule made of smaller units called nucleotides that form a chain.  If the two strands of a DNA molecule are separated, each can be used as a pattern or template to produce a complementary strand. Each template and its new complement together then form a new DNA double helix, identical to the original. Before a cell divides, its DNA is replicated (duplicated.) Because the two strands of a DNA molecule have complementary base pairs, the nucleotide sequence of each strand automatically supplies the information needed to produce its partner. Genes are made of a chemical called DNA, which is short for 'deoxyribonucleic acid'. The DNA molecule is a double helix: that is, two long, thin strands twisted around each other like a spiral staircase. The DNA double helix showing base pairs. The sides are sugar and phosphate molecules. The rungs are pairs of chemicals called 'nitrogenous bases', or 'bases' for short DNA structure. DNA is made up of molecules called nucleotides. Each nucleotide contains a phosphate group, a sugar group and a nitrogen base. The four types of nitrogen bases are adenine (A), thymine (T), guanine (G) and cytosine (C). The order of these bases is what determines DNA's instructions, or genetic code. Nucleotides are attached together to form two long strands that spiral to create a structure called a double helix. If you think of the double helix structure as a ladder, the phosphate and sugar molecules would be the sides, while the bases would be the rungs. DNA is a long molecule made up of twisted strands of the bases A, T, C and G. Genes are sections of the DNA and each gene has the code for creating a specific protein. The sequence of bases in the gene controls which amino acids are created and joined to make a specific new protein or enzyme molecule. If A occurs in one strand of a DNA molecule it will form a bond with T in the other strand. C and G will also only bond with each other. In this way it's possible to predict the order of bases on the other strand if the bases on one strand are known. Each base is also attached to a sugar molecule and a phosphate molecule. Together, a base, sugar, and phosphate are called a nucleotide. Nucleotides are arranged in two long strands that form a spiral called a double helix. The structure of the double helix is somewhat like a ladder, with the base pairs forming the ladder’s rungs and the sugar and phosphate molecules forming the vertical sidepieces of the ladder. DNA is a double helix formed by base pairs attached to a sugar-phosphate backbone. DNA, or deoxyribonucleic acid, is the hereditary material in humans and almost all other organisms. The two DNA strands are known as polynucleotides since they are composed of simpler units called nucleotides. Each nucleotide is composed of a nitrogen-containing nucleobase —either cytosine (C), guanine (G), adenine (A), or thymine (T)—as well as a monosaccharide sugar called deoxyribose and a phosphate group. Transcription is carried out by a DNA-dependent RNA polymerase that copies the sequence of a DNA strand into RNA. To begin transcribing a gene, the RNA polymerase binds to a sequence of DNA called a promoter and separates the DNA strands. DNA. DNA (or deoxyribonucleic acid) is the molecule that carries the genetic information in all cellular forms of life and some viruses. It belongs to a class of molecules called the nucleic acids, which are polynucleotides-that is, long chains of nucleotides. Each nucleotide consists of three components: 1  a nitrogenous base: cytosine (C), guanine (G), adenine (A) or thymine (T). 2  a five-carbon sugar molecule (deoxyribose in the case of DNA). Deoxyribonucleic acid (/diˌɒksiˌraɪbɵ.njuːˌkleɪ.ɨk ˈaesɪd/ ; ˈæSɪD) dna is a molecule that carries most of the genetic instructions used in the, development functioning and reproduction of all known living organisms and many. viruses Transcription is carried out by a DNA-dependent RNA polymerase that copies the sequence of a DNA strand into RNA. To begin transcribing a gene, the RNA polymerase binds to a sequence of DNA called a promoter and separates the DNA strands.
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what are the molecules in a dna strands called