How healthy cells divide - transcript
How healthy cells divide – transcript
Voiceover – Here is a cell, one of millions in the body. Within the cell's nucleus are chromosomes made of DNA. Chromosomes contain genes, the cell's instructions. Most human cells have 46 chromosomes (23 pairs), but only one is shown here. When a cell gets ready to divide its DNA is copied...
The cell checks whether everything is okay with the DNA. Is it damaged? Has it been copied correctly?
If everything is correct, then the cell can continue.
The cell gets ready to divide. It builds a molecular scaffold, called the spindle, which attaches to the DNA. The cell checks whether everything is okay with the spindle. Is the DNA attached properly?
If everything is correct, then the cell can divide. The cell splits, forming two new cells. Healthy new cells divide in a controlled way, replacing damaged or dead cells as needed. This process happens millions and millions of times every day in your body.