Where is ribose sugar found

The nitrogen bases in DNA are the basic units of genetic code, and their correct ordering and pairing is essential to biological function.

The four bases that make up this code are adenine A , thymine T , guanine G and cytosine C. Bases pair off together in a double helix structure, these pairs being A and T, and C and G.

RNA molecules, by comparison, are much shorter 3. Eukaryotic cells, including all animal and plant cells, house the great majority of their DNA in the nucleus, where it exists in a tightly compressed form, called a chromosome 4.

This squeezed format means the DNA can be easily stored and transferred. In addition to nuclear DNA, some DNA is present in energy-producing mitochondria, small organelles found free-floating in the cytoplasm, the area of the cell outside the nucleus. The three types of RNA are found in different locations. If it receives the correct signal from the ribosome, it will then hunt down amino acid subunits in the cytoplasm and bring them to the ribosome to be built into proteins 5.

Ribosomes are formed in an area of the nucleus called the nucleolus, before being exported to the cytoplasm, where some ribosomes float freely.

Other cytoplasmic ribosomes are bound to the endoplasmic reticulum, a membranous structure that helps process proteins and export them from the cell 5. Meet The Author. Ruairi J Mackenzie. Chosen for you. The chair form of ribose follows a similar pattern as that for glucose with one exception.

Since ribose has an aldehyde functional group, the ring closure occurs at carbon 1, which is the same as glucose. See the graphic on the left. The exception is that ribose is a pentose, five carbons.

Therefore a five membered ring is formed. The -OH on carbon 4 is converted into the ether linkage to close the ring with carbon 1. This makes a 5 member ring - four carbons and one oxygen. The chair structures are always written with the orientation depicted above to avoid confusion. This molecule forms part of the sugar-phosphate backbone of RNA, molecular workhorses within cells responsible for reading and carrying out instructions encoded in DNA. Yoshihiro Furukawa, a geochemist at Tohoku University in Sendai, Japan, and colleagues found the ribose, along with several chemically similar sugars, in samples from two meteorites, one collected from Morocco, the other from Australia.

The team suspects that the sugars formed from chemical reactions between water and formaldehyde in the meteorites long ago.

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