Two statements, Assertion and Reason are given. Choose the correct option from the following. Assertion: In the secondary structure of RNA, double helix structure is formed. Reason: In the double structure of RNA, two nucleic acid chains are wound about each other and held together by hydrogen bonds between pairs of bases
The correct answer is Option A: Assertion is correct but Reason is incorrect. Here's why: Assertion: In the secondary structure of RNA, double helix structure is formed. This assertion is correct. RNA, like DNA, can form double helix structures. These structures are often short and localized, and they involve base pairing between complementary nucleotides within the same RNA molecule. This is a crucial aspect of RNA's secondary structure, giving it specific shapes and functions. Reason: In the double structure of RNA, two nucleic acid chains are wound about each other and held together by hydrogen bonds between pairs of bases. This reason is incorrect. While it accurately describes the structure of DNA, it doesn't apply to the double helix formations found in RNA. In RNA's double helix, it's not two separate chains winding around each other. Instead, it's a single RNA molecule folding back on itself, forming a stem-loop structure. This stem-loop consists of a double-stranded region (the stem) and a single-stranded loop. The stem is held together by hydrogen bonds between complementary bases within the same RNA molecule. In summary, RNA does form double helix structures as part of its secondary structure, but this is due to a single RNA molecule folding back on itself, not two separate chains winding around each other.