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Carnegie Stage 3 - First Trimester
End of embryonic period

SIZE: 23.0 - 26.0 mm

TIME PERIOD: 56 - 60 days post-ovulation

Head and Neck
Head is erect and rounded. External ear is completely developed. The eyes are closed, but the retina of the eye is fully pigmented. The eyelids begin to unite and are only half closed. Taste buds begin to form on the surface of the tongue. The primary teeth are at cap stage. Bones of the palate begin to fuse. Scalp plexus reaches head vertex.

Intestines begin to migrate from the umbilical cord into the body cavity.

External genitals still difficult to recognize.

Upper and lower limbs are well formed. Fingers get longer and toes no longer webbed and all digits are separate and distinct.

Spine, Skeleton, and Muscles
Layer of rather flattened cells, the precursor of the surface layer of the skin, replaces the thin ectoderm of the embryo. Tail has disappeared.aller.

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