Question

The __________ refers to two single-stranded regions on opposite strands connecting two adjacent base-paired segments.

(a) hairpin loop

(b) interior loop

(c) pseudoknot loop

(d) helical junctions

The question was posed to me by my college professor while I was bunking the class.

I would like to ask this question from Types of RNA Structures in portion RNA Structure Prediction of Bioinformatics

Answer 1

Right choice is (b) interior loop

To elaborate: In addition to the traditional secondary structural elements, base pairing between loops of different secondary structural elements can result in a higher level of structures such as pseudoknots, kissing hairpins, and hairpin–bulge contact. A pseudoknot loop refers to base pairing formed between loop residues within a hairpin loop and residues outside the hairpin loop.