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Little One Pregnancy Calendar & Journal

Baby’s Pregnancy Calendar


Germ Layers of the Embryo

14 days old / 4 weeks pregnant (since LMP)
From The Biology of Prenatal Development.Buy Now

Note:

Starting about 2 weeks after fertilization, my right side can be distinguished from my left, and my head end from my lower back.

Label Key:

  • 1. cross section of embryo
  • 2. head end
  • 3. left side
  • 4. right side
  • 5. end close to future lower back, sometimes called the "tail" end
  • 6. plane of midline symmetry

Hide Labels | Larger | Play Movie #9
Germ Layers of the Embryo
Germ Layers of the Embryo
Tube-Shaped Heart
Tube-Shaped Heart
Three-Week Embryo
Three-Week Embryo
The Folding of the Embryo
The Folding of the Embryo
Heart Chambers and Liver
Heart Chambers and Liver
Heart in Slow Motion
Heart in Slow Motion
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