BIOMOLECULES AND ENZYMES

Detailed explanation-1: -Unlike DNA, RNA is usually single-stranded. Additionally, RNA contains ribose sugars rather than deoxyribose sugars, which makes RNA more unstable and more prone to degradation. RNA is synthesized from DNA by an enzyme known as RNA polymerase during a process called transcription.

Detailed explanation-2: -There are two reasons why RNA is generally single-stranded: RNAses are extremely abundant in most cells. Usually, double-stranded RNA is associated with a viral infection and is destroyed rapidly. Double-stranded RNA is not as stable as double-stranded DNA.

Detailed explanation-3: -Although RNA is a single-stranded molecule, researchers soon discovered that it can form double-stranded structures, which are important to its function.

Detailed explanation-4: -RNA molecules differ from DNA molecules in several important ways: They are single stranded rather than double stranded; their sugar component is a ribose rather than a deoxyribose; and they include uracil (U) nucleotides rather than thymine (T) nucleotides (Figure 4).