Question 3

DNA stores hereditary information; RNA is used to make proteins.

DNA is primarily responsible for storing and transmitting genetic information, while RNA plays a crucial role in protein synthesis by serving as a template for translating genetic instructions into proteins.

A) DNA stores hereditary information; RNA is used to make proteins.

This option correctly identifies the primary functions of DNA and RNA. DNA's role as the storage of genetic information is well-established, and RNA's function in protein synthesis is fundamental to cellular biology, making this comparison accurate.

B) DNA uses the base uracil; RNA uses the base thymine.

This statement is incorrect as it inaccurately assigns the bases to DNA and RNA. In reality, DNA contains thymine, while RNA contains uracil. Thus, this option does not correctly compare the two nucleic acids.

C) DNA is single stranded; RNA is double stranded.

This option is also incorrect. DNA is typically double-stranded, forming a double helix, whereas RNA is usually single-stranded. Therefore, this comparison does not hold true.

D) DNA is a monomer; RNA is a polymer.

This statement is misleading. Both DNA and RNA are polymers made up of nucleotide monomers. DNA is a polymer of deoxyribonucleotides, while RNA is a polymer of ribonucleotides. This option fails to provide an accurate comparison.

Conclusion

Option A is definitively correct as it accurately describes the distinct yet complementary roles of DNA and RNA in biology. The other options fail to correctly represent the structural and functional characteristics of these nucleic acids, making them incorrect comparisons.