Скачать или смотреть How Cells Divide and How Chemotherapy Works

A cell is the functional basic unit of life, often called the building block of life.
Humans have about 100 trillion cells.
You body is constantly producing new cells.
In this program, we will discuss how cells divide, how chemotherapy affects cells that are dividing, and how chemotherapy affects cancer cells.
When a normal cell divides, it goes through a series of steps, including a duplication of its DNA, which contains the genetic instructions used in the development and functioning of living organisms.
The end result of the cell division is the formation of two identical daughter cells.
Let's begin to explore how this process happens.
The cell goes through many distinct steps as it divides.
After a cell's initial formation, it goes into an inactive resting phase called G zero.
The cell then grows larger in size and makes proteins. These are important for the next step. This phase is called G1.
The cell creates two copies of its DNA in preparation for dividing. This is called the S phase.
After a second growth phase called G2, the cell continues to grow and make more proteins for the final stage.
The cell finally splits into two cells and the two copies of DNA are distributed equally between the two daughter cells. This is called the M phase or mitosis.
This completes the process of cell division.
In normal cells, there are checkpoints at every stage of this process to make sure that cells grow and divide in a regulated way. In cancer cells, these checkpoints are broken, and cancer cells grow out of control.
Chemotherapy drugs act in many different ways to disrupt cell division.
Some chemotherapy drugs can act on resting cells, as well as actively dividing cells.
Other chemo drugs can act on cells only during specific stages of the cell cycle.
For example, some chemo drugs bind to DNA exactly when the cell is making a copy of its DNA.
By preventing the cell from making a second copy of the DNA, the drugs stop the cells from dividing.
Other chemo drugs prevent cells from splitting into two daughter cells.
They prevent the DNA from being equally divided between the two cells,
Thereby preventing cell division.
Cancers are formed when abnormal cells divide rapidly without any control.
Because chemotherapy drugs target different steps during the process of cell division,...
They are good at killing cells that are dividing rapidly, like cancer cells.
Chemotherapy drugs can also damage normal cells that are dividing rapidly and this can cause side effects like hair loss.