From Layers to Life: A Developmental Journey

Your entire body, from your brain to your bones, started as just three simple layers.

The outer layer, the ectoderm, creates your skin and your entire nervous system.

The middle layer, the mesoderm, is the ultimate builder, forming your heart,

muscles, and skeleton. The inner layer, the endoderm, lines your gut and

lungs. But it gets weirder. Some cells from that outer layer, called neural crest

cells, break off and migrate, becoming everything from parts of your face to the pigment

in your skin. It’s a wild developmental journey from a simple blueprint to a complex being.