AN S 345 Lecture Notes - Lecture 22: Bone Marrow, Bone, Osteoclast

• School: Iowa State University
• Department: Animal Science
• Course: AN S 345
• Professor: Gabler Nick

Document Summary

Bone formation becomes a replacement of connective tissue. The mesenchymal cells at the site of bone formation differentiate directly into osteoblast. Osteoblast on connective tissue produce collagen fibers and bone matrix. Osteoblasts differentiate into osteocytes and produce bone. Whole process occurs like rings in a tree progressive (the more inner the rings the older) There is a central canal and then rings form around it. Appositional growth is how the rings are formed. New osteon produced (basic functional unit of compact bone) The more inner parts of the rings are going to be older bones. Does not contain true ostiones like cortical (hard, compact or lamellar) bone. Spaces between trabeculae are filled with red bone marrow. Red bone marrow produces red blood cells. A very metabolically active bone that allows for rapid turnover of minerals to help coat the eggs being produced. Critical function: osteoclasts can remove bone at the inner surface and enlarging the marrow cavity.