How Does Hair Know When To Stop Growing?..?

Question

I was asked today how does Hair stop growing?... the question i was asked was... My cats hair never grows it always stays the same length , even if i cut a piece of it it grows back to the same length again and stops. How does hair know when to stop growing?

i know strange question but if anyone has any insight or ideas please feel free to add =] thanks.

Answer 1

As hair grows it forms a bulb in the hair follicle that keeps it from falling out easily.  However the cell division within the hair follicle (that constantly pushes out the hair shaft) goes through a periodic growth and rest cycle.  During the rest part of the cycle cell division stops and the hair is prone to being pulled out (but not from a dead taxidermied animals because they don't move?).  Thus cat hairs and whiskers have their own natural lengths between rest cycles.

Answer 2

It doesn't stop growing

It gets to a certain length (lifespan of a root) and then it falls out and is replaced. This constant cycle is what gives the illusion of never growing past a certain point.

Answer 3

human hair never stops growing but i dont know. i suppose its different with animals

Answer 4

here goes:

whenever the cells move faster they grow faster wich makes hair grow taller and to make cells move faster people should train their brain...maybe cats got certain amount of cells?

Answer 5

It never stops growing and even after you're dead, it keeps growing for a while.

Answer 6

its natural.

Answer 7

when u die your body has no water so the hair neeeds water to grow but then after a while your hair starts to fall out ok byyyyyyyyyyyyyeeeeeeeeee

Answer 8

it may seem as though its not growing but it is. Hair falls out after a certain time.It does not know when to stop growing.