<P> The chemical structure of RNA is very similar to that of DNA, but differs in three main ways: </P> <Ul> <Li> Unlike double - stranded DNA, RNA is a single - stranded molecule in many of its biological roles and has a much shorter chain of nucleotides . However, RNA can, by complementary base pairing, form intrastrand (i.e., single - strand) double helixes, as in tRNA . </Li> <Li> While DNA contains deoxyribose, RNA contains ribose (in deoxyribose there is no hydroxyl group attached to the pentose ring in the 2' position). These hydroxyl groups make RNA less stable than DNA because it is more prone to hydrolysis . </Li> <Li> The complementary base to adenine in DNA is thymine, whereas in RNA, it is uracil, which is an unmethylated form of thymine . </Li> </Ul> <Li> Unlike double - stranded DNA, RNA is a single - stranded molecule in many of its biological roles and has a much shorter chain of nucleotides . However, RNA can, by complementary base pairing, form intrastrand (i.e., single - strand) double helixes, as in tRNA . </Li> <Li> While DNA contains deoxyribose, RNA contains ribose (in deoxyribose there is no hydroxyl group attached to the pentose ring in the 2' position). These hydroxyl groups make RNA less stable than DNA because it is more prone to hydrolysis . </Li>

Describe how the three types of rna work together to form protein