How do cells know to divide?

Question

I'm wondering how a cell knows how to divide? How does a heart know to pump blood without us thinking about it? What keeps our internal system working?

Answer 1

cells usually divide when they sense that they NEED to.

As in, if most of the cell parts start to malfunction, and the should get rid of them using lysosomes, or when there is too much "information going in and out of the cell, then the cell is under a lot of pressure, and that's why it needs to form two new daughter cells to handle the pressure better than just one cell.

Answer 2

In the fetus and the growing child, cells are under the influence of hormones. In a fully grown person, cells stop dividing when there is no room to grow into. It is called contact inhibition. Cell division occurs mainly at wound repair. Cancer cells lose the inhibition and divide uncontrollably.

Answer 3

About the cells - there is a group of proteins called the cyclins, and levels of different cyclins build up over time and once they hit a certain level, the cell starts dividing. After that the cell starts getting rid of the cyclins back down to their original level. It's actually way more complicated than that, but that's the short answer.

Heartbeat is controlled by parts of the nervous that we're not conscious of, just like how your intestines and your lungs work without you thinking about them. The heart also contains its own pacemaker, which is a bunch of cells called the sinoatrial node that generate electric pulses. The pulses are caused by sodium and potassium ions being pumped back and forth through the cell membranes. Sometimes people with heart problems have to get artificial pacemakers implanted to replace the natural ones.

And I have no idea what you mean by "internal system".  

Answer 4

I believe God created and designed them to work autonomically, with his direction.  

Answer 5

Its called neuromuscular junctions.  The place where neurons and muscles connect.  Thats how the heart knows how to pump.  Cells know to divide by time.  Just like when your body tells you its time to pee.

Answer 6

Somebody has it very nicely in here . But there is so much we don't know.

Answer 7

An atom knows EVERYTHING to keep you on automatic functioning

Answer 8

when it get too large, it eventually forms into 2 cells , your heart has involuntary muscles, to work by itself