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.
Like DNA, the backbone of RNA consists of a sugar molecule and a phosphate group; the difference is that in RNA the sugar is ribose, whereas in DNA it's deoxyribose.he molecules that make up RNA form long chains. Each individual unit consists 3 parts: * a nitrogenous base (cytosine, guanine, adenine, or uracil) - â¦ this is important for making the RNA code for an amino acid, essentially this is where the information is transmitted by the RNA.