Do the chromosomes ever stop copying themselves?

Question

Hello.

I know that, in humans, once the sperm and the egg is fertilized, there are 46 chromosomes, 23 from the mother and 23 from the father. Then, those chromosomes copy themselves and continue to do so until the baby is finally formed. Then the baby is ready to be born.

Now, from now on is where I would like some clearing out.

When the baby is born, I guess that the chromosomes keep on copying themselves until the baby has grown up. However, when the baby's body is fully formed (like at 18-20 or somewhere near that age) do the chromosomes keep on copying? If yes, why do they do that?

Also, once the baby is born, do the chromosomes copy themselves slower than when they were in the mother's belly?

Thank you for all of your answers.

=]

Peace.

=]

Answer 1

http://en.wikipedia.org/wiki/Chromosome

hope it helped

Answer 2

Chromosomal copying is just one of the many important processes than make cell division possible.

Your cells divide very often when you're gestating (before you're born) and afterwards as you grow and mature.

However, throughout your life, your cells continue to die and need to be continually replaced. For this reason, cell division must carry on and your cells will need to keep copying thier chromosomes.

Hope that helps!

Answer 3

Yes.  Our chromosomes are continually copying themselves in a process called Mitosis.  Basically, we are making new cells every day.  Our hair is still growing, we make LOTS of skin cells, we make blood cells, etc. etc.  Every new cell that is made went through mitosis.  And in mitosis, all the chromosomes are copied in order to form the new cell.  As you age, mitosis occurs less frequent in certain parts of your body.  For example, you stop growing taller so bone cells aren't being made as much as say...your skin cells.

And about chromosomes copying slower, it doesn't happen "slower" so to speak.  Instead, it will happen less often.  The question here is this, what kind of cells are you looking at in particular?  

Answer 4

An understanding of a cell cycle will be able to answer your queries.

G1------> S phase --------> G2---------> Mitosis or Meiosis

S phase is when a cell multiplies its genetic materials as preparation for cellular division(Mitosis or Meiosis)

G1 and G2 phases are two periods within the cell cycle when the cell gathers all the necessary resources and determines whether it will continue to divide. All these instructions and information are embedded within the DNA codes. If the cell decides to cease its growth, then it shall enter a phase known as G0 phase such as our neuronal tissues.

However, cell cycle proceeds as usual for parts for our body where wear and tear occurs such as our colonic epithelial tissues or our epidermal skin layer.

As for the speed of replication for the chromosomes, there is no difference in respect to spatial and temporal variation.