Question

There are certain times in the cell cycle when a normally operating cell stops to make sure that cell division is proceeding safely and that the cell should continue in the cycle to eventually divide into 2 cells. These times are called

Answer 1

The specific times in the cell cycle where a cell assesses whether to proceed with division are called checkpoints. These checkpoints exist to maintain the cell's DNA integrity and prevent cell cycle progression under unfavorable conditions, thereby preventing mutations and cancer. The three main checkpoints are located near the end of G1, G2/M transition, and during metaphase.

Step-by-step explanation:

There are specific times in the cell cycle when a cell will halt its procession to ensure that cell division is proceeding safely and that the continuation of the cycle towards producing two daughter cells is appropriate. These critical points are known as checkpoints. The cell cycle, which consists of ordered series of events such as growth, DNA replication, and division, has built-in mechanisms to monitor and regulate its progress. The three main checkpoints are located near the end of G1, at the G2/M transition, and during metaphase.

The function of these checkpoints is to maintain the integrity of the cell's DNA and to prevent any compromised cell from continuing to divide, which could lead to mutations and potentially cancer if unregulated. The internal controls at these checkpoints can halt the cell cycle until favorable conditions are met or can give the go-ahead when the cell is ready to proceed. These controls involve complex interactions between various regulatory molecules, including growth factors, cyclins, and cyclin-dependent kinases (Cdks), along with tumor suppressor proteins which act as negative regulators.

Answer 2

The specific times in the cell cycle when a cell checks and assesses whether to proceed with division are called checkpoints. These are crucial for maintaining the correct function of the cell and preventing issues like cancer.

Step-by-step explanation:

There are specific points during the cell cycle where a normally operating cell stops to assess whether cell division is proceeding safely and whether to continue towards division. These points are known as checkpoints.

The major checkpoints are found near the end of G1, at the G2/M transition, and during metaphase. At these checkpoints, internal control mechanisms ensure the cell is ready to proceed to the next phase, monitoring factors like DNA damage and replication completeness. If conditions are not favorable, the cell cycle can be halted by negative regulator molecules such as tumor suppressor proteins. Conversely, positive regulator molecules like cyclins and cyclin-dependent kinases (Cdks) can advance the cycle once all requirements are met.

The cell division process is integral for growth and maintenance of healthy tissues, and when regulated improperly, it can lead to cancer, characterized by uncontrolled cell division.