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.
In the 1400s Johannes Gutenberg of Germany invented a new method of printing. It used movable type-metal letters that could be arranged and rearranged to form words. It also used a machine called a press. His method was so good that very few improvements were made to it for 400 years afterward.