What´s the difference between compact bone and spongy bone?

Question

Also could you describe their spatial relationship to each ohter?

Answer 1

Examine this slide by eye. There is no endochondral ossification here; this specimen may be articular cartilage or in an area in a vertebra where bone and cartilage lie adjacent to each other.

Compare this slide with the previous one of compact bone. Identify the bony spicules or trabeculae. Observe the osteocytes. The trabeculae are thin enough so that the osteocytes can be nourished directly from the narrow space through the canaliculi. Vessels lie primarily at the periphery of the specimen where secondary bone deposition has thickened the bone, making vascular supply necessary. In the areas surrounding the blood vessels the collagen bundles and osteocytes are distributed in lamellar fashion. These lamellae should be contrasted with those of compact bone.

This is a low power shot of spongy bone to show the trabeculae (blue arrows) of it. Notice that they are thin enogh that no haversian systems are needed for the osteocytes in the to survive. They can simply extend their caniliculli into the cavity adjacent to the tabeculae.

Blue arrows - spongy bone trabeculae