NEET Practice Questions (MCQs) with Answers & Solutions

The text states: 'DNA acts as the genetic material in most of the organisms. RNA though it also acts as a genetic material in some viruses, mostly functions as a messenger. RNA has additional roles as well. It functions as adapter, structural, and in some cases as a catalytic molecule.' So, genetic material storage is primarily for DNA.

The context states: 'DNA contains a five carbon sugar molecule called 2-deoxyribose whereas RNA contains ribose.' Deoxyribose sugar lacks an oxygen atom at the 2' position compared to ribose sugar.

The text mentions: 'Both DNA and RNA contain adenine, guanine and cytosine. The fourth base is thymine in DNA and uracil in RNA.'

The context states: 'Therefore, among the two nucleic acids, the DNA is a better genetic material. ... but DNA being more stable is preferred for storage of genetic information. For the transmission of genetic information, RNA is better.'

The criteria listed are: '(i) It should be able to generate its replica (Replication). (ii) It should be stable chemically and structurally. (iii) It should provide the scope for slow changes (mutation) that are required for evolution. (iv) It should be able to express itself in the form of 'Mendelian Characters’.' Direct involvement in protein synthesis as part of its primary structure is not explicitly listed as a criterion for genetic material itself, although genetic material needs to express characters.

The text states: 'But, RNA being a catalyst was reactive and hence unstable. Therefore, DNA has evolved from RNA with chemical modifications that make it more stable. DNA being double stranded and having complementary strand further resists changes by evolving a process of repair.'

The text explains: 'Both DNA and RNA are able to mutate. In fact, RNA being unstable, mutate at a faster rate. Consequently, viruses having RNA genome and having shorter life span mutate and evolve faster.'

The text states: 'RNA can directly code for the synthesis of proteins, hence can easily express the characters. DNA, however, is dependent on RNA for synthesis of proteins. The protein synthesising machinery has evolved around RNA.'

The text states: 'The structure of DNA is a double strand whereas RNA is a single strand molecule.' This is a key structural difference.

The 'RNA World' section mentions: 'There is now enough evidence to suggest that essential life processes (such as metabolism, translation, splicing, etc.), evolved around RNA.'