ZOO 3050 Lecture Notes - Lecture 21: Neural Crest, Axial Skeleton, Somite

• School: University of Guelph
• Department: Zoology
• Course: ZOO 3050
• Professor: Andreas Heyland

Document Summary

Intermediate mesoderm and the development of the heart and kidney. Review: role of ephrins in neural tube development, terminates, inhibitory but can also have activating effects depending on receptor. This is the reverse of epithelial mesenchymal cells. Mesenchymal cells become committed cartilage cells then become compact (what you would recognize as a bone structure) Osteoblasts will condense and form a pre-bone matrix. Then you get the hardening of the pre- bone matrix. When osteoblasts are starting to be calcified they turn into osteocytes (bone cells). Endochondral ossification: mesenchymal cells will migrate to where they end up forming bones. 2 processes in endochondrial ossification: chondrocytes stop dividing, after this is it regular division of mesenchymal cells, upon division arrest they start swelling, cells becoming hypertrophic (another word for increase in volume) Insulin-like growth factor: stimulates epiphyseal plates, at end of puberty all cartilage is replaced by bone.