Final answer:
Complementary base pairs allow single-stranded RNA to form complex three-dimensional structures through hydrogen bonds, affecting RNA's functionality in cellular processes, including protein synthesis.
Step-by-step explanation:
Complementary base pairs contribute to intramolecular base pairing within an RNA molecule by allowing the RNA to fold and create complex three-dimensional structures even though it is single stranded. In RNA molecules, adenine pairs with uracil, and cytosine pairs with guanine. Due to these base pairings, RNA can form a variety of structures such as stem-and-loop formations, which are crucial for RNA's function in processes like protein synthesis and regulation.
These intramolecular base pairings are facilitated by hydrogen bonds forming between the complementary bases within the single-stranded RNA. This allows RNA to assume its functional forms, which are integral in various cellular roles, like acting as enzymes or carrying genetic information for protein synthesis (in the case of messenger RNA or mRNA).