RNA has been found in a panoply of human body fluids: blood, urine, tears, cerebrospinal fluid, breast milk, amniotic fluid, seminal fluid and others.

Deoxyribose, or more precisely 2-deoxyribose, is a monosaccharide with idealized formula H−(C=O)−(CH2)−(CHOH)3−H. Its name indicates that it is a deoxy sugar, meaning that it is derived from the sugar ribose by loss of an oxygen atom. Deoxyribose is most notable for its presence in DNA.

Figure 26.1. 3: The cyclic form of sugars is the favored form in aqueous solution. Another important group of monosaccharides are the pentoses, containing five carbons in the chain. Ribose and deoxyribose are two pentoses that are components of the structures of DNA and RNA.

The ribose and deoxyribose monosaccharides are vital elements of RNA and DNA, which are the building blocks of life. While monosaccharides cannot be broken down into smaller sugars, disaccharides and polysaccharides are broken down into monosaccharides in processes like digestion.

sugar ribose

Ribonucleic acid (RNA) is a molecule similar to DNA. Unlike DNA, RNA is single-stranded. An RNA strand has a backbone made of alternating sugar (ribose) and phosphate groups.

The two main types of nucleic acids are DNA and RNA. Both DNA and RNA are made from nucleotides, each containing a five-carbon sugar backbone, a phosphate group, and a nitrogen base. DNA provides the code for the cell ‘s activities, while RNA converts that code into proteins to carry out cellular functions.

DNA contains the instructions needed for an organism to develop, survive and reproduce. To carry out these functions, DNA sequences must be converted into messages that can be used to produce proteins, which are the complex molecules that do most of the work in our bodies.

The sequence of the nucleotides along the backbone encodes genetic information. The four roles DNA plays are replication, encoding information, mutation/recombination and gene expression.

Each DNA strand is composed of nucleotides—units made up of a sugar (deoxyribose), a phosphate group, and a nitrogenous base. Each strand of DNA is a polynucleotide composed of units called nucleotides. A nucleotide has three components: a sugar molecule, a phosphate group, and a nitrogenous base.

Three major forms of DNA are double stranded and connected by interactions between complementary base pairs. These are terms A-form, B-form,and Z-form DNA.