Answer: Both deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) are made up of nucleotides which consist of three parts: 1  Nitrogenous Base. 2  Purines and pyrimidines are the two categories of nitrogenous bases.3  Pentose Sugar. 4  In DNA, the sugar is 2'-deoxyribose. 5  Phosphate Group. 6  A single phosphate group is PO 4 3- .nswer: Both deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) are made up of nucleotides which consist of three parts: 1  Nitrogenous Base. 2  Purines and pyrimidines are the two categories of nitrogenous bases.
AT A GLANCE: In 1440, German inventor Johannes Gutenberg invented a printing press process that, with refinements and increased mechanization, remained the principal means of printing until the late 20th century.
Johannes Gensfleisch zur Laden zum Gutenberg (/joÊËhÉËnÉ¨s ËÉ¡uËtÉnbÉrÉ¡/ yoh-HAH-nÉs GOO-tÉn-behrÉ¡; 1398 â February 3, 1468) was a German blacksmith, goldsmith, printer, and publisher who introduced printing to Europe. His introduction of mechanical movable type printing to Europe started the Printing Revolution and is widely regarded as the most important event of the modern period.