Fetal25weeks

Structure: < Click on image >

Fetal Human Brain. (Image compliments of Drs. E.C. Alvord, Jr., and A.M. Spence, Dept. of Pathology, University of Washington). This frame shows a lateral view of a 25 week old human fetus. The specimen is tilted slightly on its right side so that both occipital lobes are visible. (The frontal pole is to the left of the image). The telencephalon has expanded to cover most of the diencephalon, and the lateral fissure has formed, separating the temporal lobe from the rest of the cortex. Neither the cerebral nor cerebellar cortex has developed the folds that characterize those structures in the adult brain. Branches of the middle cerebral artery emerge from the depths of the lateral fissure.