<em>a)</em><em>All living and nonliving things consist of one or more cells.</em>
A. chemical precipitation of minerals from seawater
Answer:
Medullary cavity, epiphyses
Explanation:
During the thickening of the bone collar, the penetration of Osteoblasts into the decomposing cartilage occurs thereby replacing it with spongy bone giving rise to a primary ossification center.
Osteoclasts then brings abiut the nreak down of the spongy bone to open up the medullary cavity. The cartilage found in the epiphyses then continue to grow increasing the bone's length.
I think the answer is the Deep zone.