Since they are brand-new and don't have a history of muscle use, they would have to be weak-how then are they able to move in the first place? Something has to overpower the muscles to jump-start them...
2007-07-25 12:10:22 · 6 answers · asked by comedycatalyst 2 in Science & Mathematics ➔ Biology
Rod85---I was talking about a pre-born, not after the baby is born. A baby in the womb has no need to take a breath.
2007-07-25 12:34:27 · update #1
Plus, you gave away something in the first line when you referred to the baby kicking. They kick, move, flip, suck their fingers and toes in the womb. I'm asking what is it that initiaties that?
2007-07-26 10:45:01 · update #2
The baby moves literally, inside of the mothers uterus.
This is due, to impulses from the cortex or outer layer of the brain of the newborn....some mothers DO feel the "kicking" and others dont....however, fetuses make inspiratory efforts ( good ones) from the 24-26 week of intrauterine life...There are no specific stimulus, other than the developing brain, that is capable of "exercising" the muscles of the baby, in such a manner, that the baby is born with the minimum of force to move, breath, cry etc....
In short, there are pre birth "exercises" of the fetus, regulated by the brain, and programmed for thebasic functions..
That is the reason of muscle weakness in pre term babies..
2007-07-30 17:51:18 · answer #1 · answered by Sehr_Klug 50 6 · 0⤊ 0⤋
My best GUESS: At a predisposed time inutero and very early the autonomic nervous system controls the voluntary as well as the involuntary muscles and causes the baby to move. Once movement has started the baby continues to move. Also, prior to birth and before the baby needs to use its lungs to breath, the chest will make breathing movements just to get into practice for the blessed event. For anyone who has never watched a sonogram of a fetus it is a must do and a very humbling experience.
2007-07-30 22:06:05 · answer #2 · answered by Anonymous · 0⤊ 0⤋
I don't know if this is exactly right, but for any muscle to contract, it requires a signal, an electrical impulse, from a neuron telling it to twitch. I would imagine that as the fetus is growing and developing its neurons and muscles (neuromuscular junctions,) the action potentials begin, thus triggering muscle twitches.
So it's ultimately a development question. 6 week old fetuses don't kick because they don't have the neurons or the muscles for it. Hope it makes sense.
2007-07-30 17:46:41 · answer #3 · answered by missmo1120 2 · 0⤊ 0⤋
Your premise is false, as any pregnant mom who has ever felt her baby kick will attest.
What does "kick start" the baby is the first time he or she takes a breath. The inhalation of oxygen initiates a whole lot of changes. Not only are there immediate changes in newborn muscle tone, there are changes in skin color, heart rate, reflex irritability, and breathing. These changes account for a baby's APGAR score. See the link for more information about APGARs.
2007-07-25 19:29:34 · answer #4 · answered by rod85 6 · 0⤊ 0⤋
You don't have to "overpower" a muscle to start it. The muscle is not trying to stay still. It simply sits there. When the muscular and nerve cells are in place, electrical signals can travel to the muscles, causing them to contract.
2007-07-25 19:16:58 · answer #5 · answered by lithiumdeuteride 7 · 1⤊ 0⤋
hmmm good question. how about i ask you one???? when does a ribosome start to create protein? when does a cell begin its life cycle??? as soon as it is created. think for a second
babies - and all living organisms - are made from cells. even when the sperm has not yet met the egg they - the sperm and egg - are individually alive. once they meet mieosis begins and so does the child.
2007-08-02 15:20:50 · answer #6 · answered by neongreensugar 3 · 0⤊ 0⤋