Developmental Anatomy

Stage 10: Summary

First view Second view

External: 4-12 pairs of somites; fusion of neural folds is imminent or in progress; the opic sulcus may have appeared; pharyngeal arch 1 begins to be visible on the surface.

Internal: The cardiac loop is appearing; the laryngeotracheal sulcus develops; the intermediate meso-derm becomes visible.

Lab Manual - Horizon 10

First view Stereo view Second view

  • Length: 1.5 - 3 mm.
  • 4 -12 pairs of somites.
  • Fusion of neural folds is imminent or in progress.
  • The optic sulcus may have appeared.
  • Pharyngeal arch 1 begins to be visible on the surface.
  • The cardiac loop is appearing.
  • The laryngeotracheal sulcus develops.
  • The intermediate mesoderm becomes visible.
  • Ovulation age: 22 - 23 days.

Stage 10: Animation

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Developmental Stages in Human Embryos by Ronan O'Rahilly and Fabiola Müller.
Published by Carnegie Institution of Washington, Publication 637. 1987.

Stage 10 (PDF 582 KB)

 

QUESTION: What is the state of the neural folds?

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