Kaplan Nursing Entrance Practice Exam 2025 – The All-in-One Guide to Exam Success!

DNA is the fundamental molecule that serves as the blueprint for heredity in all living organisms. It contains the genetic information necessary for the growth, development, functioning, and reproduction of cells. The sequences of nucleotides in DNA encode the instructions for synthesizing proteins, which are essential for various cellular processes, but it is the DNA itself that is passed from parents to offspring during reproduction. This genetic material determines inherited traits, making DNA the cornerstone of heredity.

In contrast, while proteins are crucial for cellular functions and can influence genetic traits, they do not carry genetic information themselves. Ribosomes are responsible for the synthesis of proteins but do not contain genetic material; they read the information encoded in RNA to assemble amino acids in the correct order. The cell membrane serves as a protective barrier for the cell and regulates the movement of substances in and out of the cell but does not play a direct role in heredity. Thus, DNA is most directly involved with heredity.