The human embryo at 5-6 weeks,surrounded by the fluid-filled amniotic sac. The umbilical cord (carrying 2 arteries & 1 vein to the placenta) connects the embryo with the maternal circulation,supplying oxygen & nourishment & removing waste materials. Primitive organ systems have formed & are developing rapidly. The void at the back of the head awaits partial filling by a further division of the brain (at present in 3 parts,the fore-,mid-,& hindbrain),leaving the 4th ventricle under the cerebellum. The retina of the eye is visible (dark spot),the arms & legs have budded; the heart has formed & has been beating since the 3rd week | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Edelmann |
Taille de l’image : | 3628 px × 2461 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : |
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