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The Endowment for Human Development
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The Folding Heart

3 weeks, 5 days

From The Biology of Prenatal Development.Buy Now

Note:

Heart chambers begin developing quickly! It makes sense because the rapidly growing embryo requires a rapidly expanding circulatory system to survive and thrive.

Note:

The conotruncus represents the outflow tract of the heart. As development proceeds, the inflow end of the heart will become situated closer to the head as seen in the fetus, newborn, and adult.

Label Key:

1. right ventricle
2. conotruncus
3. left ventricle
4. atrio-ventricular canal (will receive incoming blood from the atria)
All ages referenced to fertilization, not last menstrual period.
The Folding of the Embryo
The Folding of the Embryo
The 4-Week Embryo
The 4-Week Embryo
The Folding Heart
The Folding Heart
Four-Week Embryo
Four-Week Embryo
Digestive Tract, 4-Week Embryo
Digestive Tract, 4-Week Embryo
The Body Plan Emerges
The Body Plan Emerges
Tell your story. Create your own pregnancy calendar.
Buy the Biology of Prenatal Development DVD