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

The correct answer is the chloroplast, which is primarily found in plant cells. Chloroplasts contain chlorophyll, a green pigment that captures sunlight during the process of photosynthesis. This process allows plants to convert light energy into chemical energy stored in glucose, which serves as food for the plant. Ultimately, chloroplasts play a vital role in the energy transformation necessary for plant growth and sustenance, reflecting their essential function within the cellular structure of autotrophic organisms.

The other organelles listed do not perform this specific function. The nucleus is responsible for storing genetic information and regulating cell activities, while the endoplasmic reticulum is involved in the synthesis and transport of proteins and lipids. The Golgi apparatus processes, packages, and distributes proteins and lipids but does not capture sunlight or convert energy. Thus, chloroplasts are uniquely adapted for the task of converting sunlight into chemical energy, highlighting their significance in the life of plants and, by extension, life on Earth.