Kaplan Nursing Entrance Exam Practice 2025 – Comprehensive Prep

A chromosome is primarily composed of DNA and proteins. This combination is crucial for the structural integrity and functional regulation of genes. DNA carries the genetic information necessary for the development, functioning, and reproduction of all living organisms. Proteins, specifically histones, play a key role by helping to package and condense the long strands of DNA into a compact form, enabling the efficient organization within the cell nucleus.

The presence of proteins in chromosomes aids in the regulation of gene expression and DNA replication. Additionally, specific proteins are involved in repairing damaged DNA, as well as in the processes of cell division. This interplay between DNA and proteins is essential for maintaining genetic stability and ensuring that genetic information is accurately passed on during cell division.

In contrast, the other combinations listed do not accurately reflect the composition of chromosomes. RNA, while important for translating genetic information into proteins, is not a structural component of chromosomes. Lipids and carbohydrates do not play a direct role in the formation or function of chromosomes either. Therefore, the correct identification of chromosomes as DNA and proteins highlights their essential roles in genetics and cellular biology.