Prenatal Bone Formation: How the Human Skeleton Begins
The First Spark: Cartilage Blueprints (Weeks 5–7) Before anything looks like a bone, tiny clusters of mesenchymal stem cells gather and start shaping soft cartilage models. These faint outlines act like early blueprints—flexible, delicate, and waiting for something more. Around week 5 from fertilization, the first wave of these tissues begins forming the structural hints […]