What term describes membrane-enclosed structures that carry out specialized functions inside a cell?

• A. Organelles
• B. Chloroplasts
• C. Ribosomes
• D. Vacuoles

Answer: (A)

Membrane-enclosed compartments carrying out specialized functions inside a cell are called organelles. This broad category includes structures like the nucleus, mitochondria, and endoplasmic reticulum, as well as chloroplasts and vacuoles found in plant cells. The key idea is that organelles are distinct, membrane-bound units each with a specific role, enabling the cell to compartmentalize processes. For example, chloroplasts are a type of organelle specialized for photosynthesis, which illustrates why the general term is needed to describe all such structures. In contrast, ribosomes aren’t surrounded by a membrane, so they aren’t organelles in this sense, even though they perform essential work inside the cell.