GED Science Practice 2026 - Free GED Science Practice Questions and Study Guide

The nucleus is commonly referred to as the brain of the cell because it contains genetic information in the form of DNA and RNA, which is essential for the cell's growth and reproduction. This makes options A, B, and D incorrect as they do not pertain to this specific function of the nucleus. Nuclear fusion refers to the process of combining two atomic nuclei to form a heavier nucleus, and nuclear reactor is a device used to initiate and control a sustained nuclear chain reaction. The optic nerve is responsible for transmitting visual information from the eye to the brain and is not related to the nucleus or its functions.