Biology / Unit 13 Bio 3085 short lesson, about 20 seconds
Endoskeleton Structure Overview
Captions available
The idea
An endoskeleton is an internal framework of bone or cartilage that grows with the body continuously, providing attachment points for muscles that pull against it from outside.
In practice
A growing child's skeleton enlarges gradually alongside surrounding tissue, unlike an arthropod's staged molt.
Where people slip
An endoskeleton still requires muscle to move it — the skeleton itself provides no motive force.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
Unlocks
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