Today Hank explains the skeletal system and why astronauts Scott Kelly and Mikhail Kornienko are out in space studying it. He talks about the anatomy of the skeletal system, including the flat, short, and irregular bones, and their individual arrangements of compact and spongy bone. He’ll also cover the microanatomy of bones, particularly the osteons and their inner lamella. And finally, he will introduce the process of bone remodeling, which is carried out by crews of osteocytes, osteoblasts, and osteoclasts.

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Chapters:
Introduction: Astronaut Bones 00:00
Structure of the Skeletal System: Axial & Appendicular Bones 2:33
Bone Shapes: Long, Short, Flat, and Irregular 3:11
Internal Bone Structure 3:47
Osteons and Their Lamellae 5:05
Osteoblasts and Osteoclasts 5:54
Bone Remodeling: Resorption & Apoptosis 7:28
Review 9:28
Credits 10:13

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