Define apoptosis.

Apoptosis is defined as programmed cell death that plays a crucial role in maintaining the health of an organism by eliminating damaged, diseased, or unnecessary cells in a controlled manner. This process involves a series of biochemical events leading to characteristic cell changes and ultimately cell death without the inflammatory response typically associated with necrosis, which is another form of cell death.

Apoptosis serves essential functions, such as shaping developing organs, maintaining tissue homeostasis, and protecting the body by eliminating potentially harmful cells, like those that are damaged or cancerous. This mechanism is tightly regulated and involves specific signaling pathways that activate caspases, which are enzymes that orchestrate the dismantling of the cell.

The options presented that describe other processes do not capture the essence of apoptosis accurately. For instance, uncontrolled cell growth characterizes cancer rather than apoptosis, while cellular inflammation does not describe cell death but rather the response of the body to injury or infection. Active cell division refers to mitosis, which is the opposite of apoptosis, as it involves cells proliferating rather than dying off. Therefore, option C presents an accurate depiction of apoptosis as a necessary and beneficial biological process.