PSI. Pounds per square inch: a unit for measuring pressure. One PSI equals the pressure resulting from a force of one pound force acting over an area of one square inch. See pound.
  The four bases that make up RNA are:   * Adenine (A)  * Cytosine (C)  * Guanine (G)  * Uracil (U).denine and guanine are complementary, as are thymine and cytosine. RNA is practically the same, â¦ except that thymine is replaced with uracil (U) - meaning that when RNA replicates DNA, any thymine needed is replaced with uracil. Uracil is still compatible with cytosine, though.
A nucleotide is made up of a sugar (deoxyribose in DNA and ribose in RNA), a phosphate and a nitrogenous base. The nitrogenous bases found in DNA are adenine (A), thymine (T â¦), cytosine (C) and guanine (G).he three components that make up the nucleotides of RNA are the nucleobases, the ribose sugars, and the phosphate backbone. The nucleobases are what give RNA its variability, â¦ denoted by the letters A, C, G and U. They form the alphabet that gets translated into the different amino acids that make up proteins.