Kaplan Nursing Entrance Practice Exam

Which biological molecule is primarily responsible for hereditary information?

1. Carbohydrates

2. Proteins

3. Enzymes

4. Nucleic acid

The correct answer is: Nucleic acid

Nucleic acids are the biological molecules primarily responsible for hereditary information because they store and transmit genetic information within living organisms. DNA (deoxyribonucleic acid) is the primary form of nucleic acid that carries the instructions for the development, functioning, growth, and reproduction of all known organisms. These instructions are encoded in sequences of nucleotides, which form genes. RNA (ribonucleic acid) also plays a crucial role in expressing this genetic information, particularly in the synthesis of proteins. In contrast, carbohydrates mainly serve as energy sources and structural components, proteins provide various functions including catalyzing biochemical reactions and acting in cell signaling, while enzymes are specifically proteins that facilitate these biochemical reactions. Therefore, while all these biomolecules are essential for various cellular processes, nucleic acids are unique in their role as the carriers of genetic information and heredity.