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Updated: May 29, 2026

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Using Ex Vivo Upright Droplet Cultures of Whole Fetal Organs to Study Developmental Processes during Mouse Organogenesis
Published on: October 21, 2015
[Development of the skeletal system in utero]
1Department of Obstetrics and Gynecology, Keio University, Japan.
Summary
The skeletal system forms from mesenchyme via endochondral or intramembranous ossification. This review details skeletal development timelines during fetal development.
Area of Science:
- Developmental biology
- Skeletal biology
- Embryology
Context:
- The skeletal system originates from mesodermal and neural crest cells.
- Bone formation is crucial for structural integrity and development.
- Understanding skeletal development provides insights into congenital skeletal disorders.
Purpose:
- To outline the developmental timeline of the skeletal system in utero.
- To describe the two primary mechanisms of bone formation: endochondral and intramembranous ossification.
- To provide a foundational overview of skeletal development for researchers and clinicians.
Summary:
- The skeletal system arises from mesenchyme derived from the mesodermal germ layer and neural crest.
- Bone development occurs through endochondral ossification (cartilage precursor) or intramembranous ossification (direct from mesenchyme).
- This review focuses on the chronological sequence of skeletal development during prenatal development.
Impact:
- Provides a clear overview of skeletal development for students and researchers.
- Highlights key processes in bone formation, essential for understanding skeletal pathologies.
- Establishes a timeline for in utero skeletal development, aiding in the study of congenital anomalies.
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