is the human skeletal system a "passive" system?

[paul]

ie, is it unlike the muscular system in that it can't move unless pulled and pushed by muscles?

 

also, are there neurons running throughout the bone tissue? and if so, what is their function (assuming that the brain can't send a signal to them to instruct them to move - in the way it can with muscles)?

[Sisyphus]

Well, they're "passive" in that none of their functions are consciously controlled, just like most of your organs (with the exception of some of your muscles). And yes, they need muscles to move. They contain nerves for the same reasons that all your organs do: to control their functions (like blood production) and to let the brain know what's going on. And of course the spine is the conduit for the spinal cord.

[Mokele]

The skeletal system has no motile properties whatsoever - it cannot move unless acted upon by an outside force, like muscles.

 

It is technically metabolically active, as cells within the bone with deposit or release calcium into the blood to regulate blood calcium levels and buffer pH, as well as constantly dissolving and redepositing bone to both heal (either breaks or minor, microscopic stress fractures) and respond to loads (strongly loaded bone, such as a pro tennis player's dominant arm bones, will hypertrophy).

 

And yes, there are nerves, but they only go to the surface layer of membrane around the bone, called periosteum, not into the bone itself, and they're purely sensory. It's actually the disruption of this membrane that hurts, not the break.

 

 

So, ultra-short version:

1) Yes, bone is mechanically passive

2) Sensory nerves surround bones, but none actually go in, nor are there motor nerves.

 

Mokele