Why does compact bone have canaliculi, but spongey bone does not?
a) spongy bone does not have osteocytes, unlike compact bone.
b) spongy bone does not require a blood supply.
c) nutrients and waste cannot diffuse through spongy bone
d) nutrients and wastes cannot diffuse through compact bone.

Peat deposits are found in waterlogged places where dead plant material piles up. when peat is buried, it undergoes compaction. it is subjected to heat and pressure for a long time, and a lot of water is squeezed out during this process. nearly ten vertical feet of original peat material becomes one vertical foot of coal. which of these remains unchanged in the system during the conversion of peat to coal? a) area b) density c) mass d) volume