Eventually, all cells need O2 and other minerals and sugar, and need a way to get rid of their waste products (CO2 for example). But yes, the metabolism of the osteocyte (the cell within the bone itself) is probably much lower than other organs (brain), but all of the bone needs to get O2 in order to function properly, otherwise bone dies. And yes, there are diseases and situations in which this happens.
Microscopically, the bone is not completely solid (even the solid looking, cortical bone). It has canaliculi that connect the cells within with each other and with the exterior, and it is through this system that they get their oxygen and rid their waste products. The cells that produce bone are called osteoblasts, and they are outside. Metabolically, they’re more active than osteocytes, but they are also closer and nearer to the bone marrow and vessels that go into the bone.
The surface of the bone, unlike the surface of the skin, is not “excreta”. All of it is living tissue, all of it needs oxygen (at various levels and needs), and without it the bone most certainly dies. Also, your bone is constantly being remodeled. At different rates throughout life, but the bone is not “static” like for example neurons or cardiac muscle.
What travels through these canalculi to carry out those function?
Are the “functional units” circulated, or are they one-way packages–from O2 pickup to O2 transfer, and then die, or change after that one transit? (As opposed to blood cells, which do eventually die, but do their stuff repeatedly for a while.)
Does the functioning of the above query (2) even exist in the human body? Or am just making this shit up, and it’s a good thing I’m not God (one of many reasons, admittedly)?
Not a query: I never knew the word canalculi…it reminds me of the animalculi he found swimming around under his scope…
Periosteocytic fluid, but I think you’ll find most of the substance flow is osteocyte-to-osteocyte via gap junctions, after initial uptake from the bone capillaries/before excretion to those caplillaries. The fluid is for the larger molecules and ions like Ca and P and proteins.
No, the canaliculi in the bones are usually too small for complete cells, they mostly contain either fluid or cellular extensions (think like arms) as mentioned above. So nothing really dies during transfer, it is either going through diffusion or active cell to cell transfer.
As mentioned, different cells have different metabolic rates and different needs, adapted to their environment. But they all, definitely, need some oxygen and some way to get rid of their waste. How much or how frequent may vary, but the need is there.
But yes, the metabolism of the osteocyte (the cell within the bone itself) is probably much lower than other organs (brain), but all of the bone needs to get O2 in order to function properly, otherwise bone dies. And yes, there are diseases and situations in which this happens.