Given below are two statements. [2023]
Statement I: RNA being unstable, mutate at a faster rate.
Statement II: RNA can directly code for synthesis of proteins hence can easily express the characters.
In the light of the above statements, choose the correct answer from the options given below.
Statement I is correct but statement II is false.
Statement I is incorrect but statement II is true.
Both statement I and statement II are true.
Both statement I and statement II are false.
Which one of the following is not applicable to RNA? [2015]
Heterocyclic nitrogenous bases
Chargaff’s rule
Complementary base pairing
5’ phosphoryl and 3’ hydroxyl ends
(2)
Chargaff’s rules are applicable only for double stranded DNA molecule. These are not applicable for single stranded DNA or RNA molecules. Chargaff’s rules state that DNA helices contain equal molar ratios of A and T, G and C. This is because in a dsDNA molecule, complementary base pairing occurs between A and T, and C and G base pairs. This complementary base pairing is not possible in case of single stranded RNA molecule. Thus, Chargaff’s rules are not applicable to RNA.
Given below are two statements : [2025]
Statement I : In the RNA world, RNA is considered the first genetic material evolved to carry out essential life processes. RNA acts as a genetic material and also as a catalyst for some important biochemical reactions in living systems. Being reactive, RNA is unstable.
Statement II : DNA evolved from RNA and is a more stable genetic material. Its double helical strands being complementary, resist changes by evolving repairing mechanism.
In the light of the above statements, choose the most appropriate answer from the options given below :
Both statement I and statement II are correct
Both statement I and statement II are incorrect
Statement I is correct but statement II is incorrect
Statement I is incorrect but statement II is correct
(1)
In RNA world, RNA was the first genetic material as there are enough evidences to suggest that essential life processes (such as metabolism, translation, splicing, etc) evolved around RNA. RNA used to act as a genetic material as well as catalyst (there are some important biochemical reaction in living systems that are catalysed by RNA catalysts not by protein enzymes) so, statement I is correct statement II is also correct as DNA being double stranded and having complementary strands further resists changes by evolving a process of repair.
