Human eye of the size of the pupil, regulation and suppression of the hormone melatonin and entrainment of the body clock. The eye is not shaped like a perfect sphere, rather it is a fused two-piece unit, composed of the anterior segment and the posterior segment. The anterior segment is made up of the cornea, iris and lens. The cornea is transparent and more curved, and is linked to the larger posterior segment, composed of the vitreous, retina, choroid and the outer white shell called the sclera. The cornea is typically about 11.5 mm (0.3 in) in diameter, and 1/2 mm (500
Development of the human cerebral cortex Development of the human cerebral cortex Corticogenesis is the process in which the cortex of the brain is created during neurodevelopment. The cortex is the outer layer of the brain and is composed of up to six layers. Neurons formed in the ventricular zone migrate to their final locations in one of the six layers of the cortex The process occurs from embryonic day 10 to 17 in mice and between gestational weeks seven to 18 in humans. The preplate is the first stage in corticogenesis prior to the development of the cortical plate. The preplate is located between the