Washington Comprehensive Assessment of Science (WCAS) Practice Test

The nucleus is the cellular structure that houses the DNA and serves as the genetic material. It is often referred to as the control center of the cell because it contains the instructions needed for cellular growth, development, and reproduction. The DNA within the nucleus is organized into structures called chromosomes, which carry the genes that dictate an organism's traits and functions. The nuclear envelope protects the DNA from damage and regulates the movement of molecules in and out of the nucleus, ensuring that the genetic information is preserved and appropriately utilized during processes like transcription and replication. This role is fundamental to the functioning of eukaryotic cells, distinguishing them from prokaryotic cells that contain their genetic material in the cytoplasm.