📚 Topic Summary
The cell cycle is a tightly regulated process, and checkpoints are critical control points that ensure proper cell division. These checkpoints—G1, S, and G2—monitor DNA integrity, chromosome replication, and spindle formation. If errors are detected, the cell cycle halts until repairs are made. In cancer cells, these checkpoints are often disabled or bypassed, leading to uncontrolled cell division and tumor formation. Understanding how these checkpoints work (or don't work!) is essential for understanding cancer biology.
🧪 Part A: Vocabulary
Match the terms with their definitions:
- Term: Apoptosis
- Term: Tumor Suppressor Gene
- Term: Proto-oncogene
- Term: Oncogene
- Term: Cell Cycle Checkpoint
- Definition: A gene that normally regulates cell division but can cause cancer when mutated.
- Definition: A control mechanism that ensures proper cell division.
- Definition: Programmed cell death.
- Definition: A normal gene that can become an oncogene due to mutations.
- Definition: A gene that regulates cell division and prevents uncontrolled growth.
(Match the terms to the correct definitions.)
🧬 Part B: Fill in the Blanks
The G1 checkpoint, also known as the ___________ checkpoint, assesses the cell's size, resources, and DNA _________. If the cell does not meet these requirements, it will enter a resting phase called _________. Proteins like ___________ play a critical role in regulating this checkpoint by monitoring DNA damage.
🤔 Part C: Critical Thinking
Cancer cells often have mutations that disable or bypass cell cycle checkpoints. Explain how the failure of these checkpoints contributes to the uncontrolled growth and division of cancer cells, and discuss potential therapeutic strategies that target these checkpoint defects.