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The Endowment for Human Development
The Endowment for Human Development
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Slideshow: The Heart

Four-Week Embryo

#35, Slide 4 of 34

4 weeks

From The Biology of Prenatal Development.Buy Now

Label Key:

1. hindbrain
2. spinal cord
3. foregut
4. heart
5. midgut
6. midbrain
7. forebrain
8. site of future mouth (stomodeum)
9. chest wall
10. yolk sac
11. hindgut
All ages referenced to fertilization, not last menstrual period.
Heart ChambersThe Folding HeartThe Folding of the EmbryoFour-Week EmbryoThe Body Plan EmergesThe Heart in MotionHeart Chambers and LiverHeart in Slow MotionSurrounded by the AmnionHeart and LiverHead and HeartHeart and BrainHead and HeartLiver, Cord, and Left Foot PlateClose-up of Heart and LiverHeart and LiverThe Heart and LiverThe Vital OrgansHand Plate and Vital OrgansLeft Hand Plate and WristThe HeartThe Brain, Heart, and LiverThe Hand in MotionThe Face and TrunkLeft Hand and Vital OrgansThe Beating Heart and LiverThe Liver and Beating HeartThe Heart and BrainThe Four-Chambered HeartThe Hand, Chest, and LiverThe Heart and HandThe Beating HeartThe Heart and ChestClose-up, Seven-Week Heart
When does health begin? Find out now.
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