Biology / Unit 13 Bio 3359 short lesson, about 20 seconds
Vertebrate Axis Formation
Captions available
The idea
Vertebrate development establishes anterior-posterior and dorsal-ventral body axes early on, through signaling gradients that tell cells at each position which structures to form there.
In practice
A signaling gradient stronger at one end of the embryo helps specify that end as anterior, or head-forming, tissue.
Where people slip
Axis formation sets positional identity for later structures — it does not itself build any organ directly.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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