AAMC FL Practice Exam

How are cancer cells characterized in relation to cell division?

1. They undergo apoptosis regularly

2. They grow and divide continuously in a regulated manner

3. They grow and divide continuously at an unregulated pace

4. They undergo a normal cell cycle

The correct answer is: They grow and divide continuously at an unregulated pace

Cancer cells are characterized by their ability to grow and divide continuously at an unregulated pace. Unlike normal cells that reproduce in a controlled manner and undergo apoptosis when necessary, cancer cells lose the regulatory mechanisms that typically restrict cell proliferation. This loss of control leads to uncontrolled growth, allowing cancer cells to proliferate much more rapidly than normal cells, contributing to tumor formation and malignancy. Moreover, cancer cells often exhibit mutations in genes that regulate the cell cycle, leading to an inability to respond appropriately to signaling that would normally halt division or initiate apoptosis. These characteristics enable cancer cells to bypass the usual checks and balances, resulting in their unregulated pace of division and growth. In contrast, regular apoptosis and a controlled cell cycle are typical of healthy cells, where various checkpoints ensure that cells only divide under favorable conditions and that damaged cells are eliminated. Thus, the properly regulated mechanisms that govern normal cell behavior are disrupted in cancer cells.