2006-09-03 06:04:08 · 8 answers · asked by mani 1 in Science & Mathematics ➔ Biology
Don't think it is based on age- I think it is based on DNA. I stopped growing at age 12, a total of 72 inches tall. My boyfriend didn't get his last inch until he was 23.
2006-09-03 06:09:51 · answer #1 · answered by sawtooth_honey 4 · 0⤊ 0⤋
We stop growing because we are through developing. Think of it like climbing a hill. When we get to the top, we're through growing. Then, it's all down hill from there.
Bones are the last part of us to finish growing. They are still developing until age 22 if I recall correctly. But this does not mean a noticeable change in height will occur in the latter teen years.
2006-09-03 13:13:04 · answer #2 · answered by Layla Clapton 4 · 0⤊ 0⤋
All animals, including humans, have evolved to stop growing at a size that balances energy efficiency and their competitive needs as they struggle to survive. Among individuals, when you stop growing and how tall you end up are predetermined by your genes. Growth occurs when cells called chondroblasts multiply and add cartilage to the ends of bones. Cells called osteoblasts then deposit calcium and other minerals in the cartilage and turn it into new bone. As more cartilage gets deposited and mineralized, bones become longer and you get larger. Toward the end of puberty in both males and females, your body produces lots of estrogen, which inhibits chondroblast proliferation and slows the addition of new cartilage to the end of your bones. When all the cartilage in the active-growth area is calcified, you stop growing. The overproduction or underproduction of certain hormones, or the inability to respond to them, can affect whether you grow more or less than normal. Gigantism is caused by the overproduction of pituitary growth hormone, whereas severe short stature is often caused by the body's inability to respond to this and other growth hormones.
2006-09-03 13:22:15 · answer #3 · answered by Andy S 6 · 1⤊ 0⤋
simple... its gene regulation...
hope u might knew the genes are turned on and off by many factors... likewise the growth ceases after attaining puberty where the growth stops in height... but conciderably it accerlarate in other things... like peaken with the sexual hormones rather than growth hormone...
so this phenomenon is regualted by gene expression... so thats why... hormone changes with external cues and the internal regulation is maintained by gene regulation
2006-09-03 16:16:15 · answer #4 · answered by alwin 2 · 0⤊ 0⤋
Genetics.
2006-09-03 16:12:45 · answer #5 · answered by The One 3 · 0⤊ 0⤋
Our bones become fully developed and our hormones don't do as much.
2006-09-03 13:09:55 · answer #6 · answered by Armin 2 · 0⤊ 0⤋
these all bcoz due to hormonal changes
2006-09-06 00:46:54 · answer #7 · answered by Anonymous · 0⤊ 0⤋
idk i think after u hit puberty u grow like a couple inches more than stop
2006-09-03 13:09:18 · answer #8 · answered by nathan'87 3 · 0⤊ 0⤋