Compare the functions of a normal cell and that of a cancer cell with regards to cell division. Discuss the cell cycle control system and checkpoints and how these might be altered in a cancer cell.
Since this is not my area of expertise, I searched Google under the key words "mitosis body cells cancer " to get these possible sources:
http://www.biology.iupui.edu/biocourses/N100/2k4ch8mitosisnotes.html
http://www.biology.iupui.edu/biocourses/N100H/ch8mitosis.html
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/C/Cancer.html
http://www2.bc.cc.ca.us/jfulks/Bio%2032_mitosis_and_cancer.htm
In the future, you can find the information you desire more quickly, if you use appropriate key words to do your own search.
I hope this helps. Thanks for asking.
To compare the functions of a normal cell and a cancer cell with regards to cell division, let's first understand the cell cycle control system and checkpoints.
The cell cycle is a highly regulated process that allows cells to grow, divide, and maintain proper function. It consists of several phases, including the G1 phase (gap 1), S phase (synthesis), G2 phase (gap 2), and M phase (mitosis). The cell cycle control system ensures that each phase occurs in the right order and that the cell progresses to the next phase only when conditions are favorable.
At specific points in the cell cycle, there are checkpoints that act as control mechanisms to monitor the integrity of the DNA, verify cell size, and assess external signals before allowing the cell to proceed to the next phase. These checkpoints exist to prevent errors such as DNA damage or insufficient cell size from being passed on to daughter cells. The key checkpoints are the G1 checkpoint, G2 checkpoint, and the mitotic checkpoint at the end of metaphase.
Now, let's discuss the differences between a normal cell and a cancer cell in terms of cell division and the cell cycle control system.
Normal cells carefully follow the cell cycle control system, ensuring that cell division occurs in a controlled and regulated manner. They enter the cell cycle when stimulated by appropriate signals, progress through each checkpoint, and divide only when conditions are suitable.
In contrast, cancer cells have abnormalities in cell division. They show uncontrolled and rapid cell division, leading to the formation of tumors. These cells often bypass the checkpoints and fail to regulate the cell cycle properly. This aberration in cell division arises due to the accumulation of genetic mutations, which can impair the function of key proteins involved in cell cycle regulation.
For example, at the G1 checkpoint, normal cells check for DNA damage and assess growth factors to ensure sufficient size for division. Cancer cells may acquire mutations that disrupt these controls, allowing them to pass through the checkpoint despite having damaged DNA or being undersized.
Similarly, at the G2 checkpoint, normal cells assess DNA integrity before entering mitosis. Cancer cells may have mutations that disable or weaken this checkpoint, causing them to proceed to mitosis even if the DNA is damaged.
Lastly, the mitotic checkpoint ensures proper alignment of chromosomes during cell division. When this checkpoint malfunctions, cancer cells can divide with an abnormal number of chromosomes, which can lead to further genetic instability and tumor progression.
In summary, the cell cycle control system and its checkpoints play a vital role in regulating cell division in normal cells. However, cancer cells often exhibit alterations in these checkpoints, allowing them to divide uncontrollably and contribute to tumor formation. It is through the understanding of these differences that researchers aim to develop targeted therapies to address the specific vulnerabilities of cancer cells.