Human bones have a hard outer layer made of condensed bone and a softer inner core of spongy bone. This landscape of blue, red, and gold is a cross section through a developing human bone. Human bones ...

Medically reviewed by Gagandeep Brar, MD Bone marrow is the deep, interior portion of your bone. Your bone marrow, which has ...

but differences in their makeup and function set them apart. For instance, teeth contain enamel, a substance much harder than bone. Despite their solid appearance, bones contain a spongy inner ...