Which of the following structures is unique to plant cells?

Chloroplasts are the structures that are unique to plant cells. They are integral to the process of photosynthesis, allowing plants to convert sunlight into energy by synthesizing glucose from carbon dioxide and water. This function is crucial for plants, as they are primary producers in ecosystems, providing energy for a wide range of organisms.

While cell membranes, nuclei, and ribosomes are found in both plant and animal cells, chloroplasts specifically serve as the site for photosynthesis and contain chlorophyll, the pigment that captures light energy. This distinct role of chloroplasts not only enables plants to produce their own food but also contributes to the oxygen output crucial for life on Earth, highlighting their unique presence in plant cells.