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.
(2) DNA is made up of these four bases: adenine & guanine, cytosine & thymine; R â¦ NA is made up of adenine & guanine, cytosine & URACIL, the difference being that in RNA, uracil replaces thymine. (3) DNA is a double stranded molecule, and RNA is a single stranded molecule. The sugar in RNA is ribose, and in DNA the sugar is deoxyribose. - RNA is usually single stranded, DNA is double-stranded helix. - RNA contains uracil instead of thymine. DN â¦ A does contain thymine.