What is an organelle?

An organelle is defined as a specialized part of a cell that has a specific function. This is essential for proper cellular operation since organelles perform distinct tasks that contribute to the overall health and efficiency of the cell. For example, mitochondria are organelles that produce energy, while ribosomes are responsible for protein synthesis. Each organelle contributes to the cell's functionality, allowing it to grow, reproduce, and respond to its environment.

The other options do not accurately describe what an organelle is. A harmful substance refers to toxins or chemicals that can damage living organisms. A term associated with hospitals typically involves medical care or treatment rather than cellular components. A dental specialty would pertain to specific areas of dentistry, which also do not relate to the cellular biology context of organelles. Hence, the definition that identifies an organelle as a specialized component of a cell is the only one that correctly captures its role in biology.