Ribo-This is short for ribose and it is a pentose sugar. Contrast this with the sugar group in DNA which is dexoyribose. Nucleic-Refers to the fact that it originates in the nucleus.
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 shape of DNA is normally described as a double-helix, which is two strands twirled loosely around each other. The DNA molecule is shaped like an extremely long ladder twisted into a helix, similar in appearance to the shape of a spiral stairway.