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
History of beliefs about the human body body has in the world. All cultural ideals of the body in the early modern period deal with deficiencies and disorders within a body, commonly told through a male ideal. Ideas of the body in the early modern period form the history of how bodies should be and how to correct the body when something has gone wrong. Therefore, early modern conceptions of the body were not biological as there was not a restrictive biological view of the human body as established by modern science. Conceptions of the body are primarily either eastern, based in China and involving practices such