Derived from the coca plant. Other names for cocaine include, but are not limited to coke, snow, lady, flake, gold dust, freebase and crack. Cocaine is derived from the leaves of the coca plant, found in South America. The leaves are mashed, much like grapes are for making wine, then are treated with sulfuric acid. During this process, the active drug is released, as a paste is formed.
The fovea is an important region of the retina, as it contains the highest concentration of photoreceptors in the eye. Nervous tissue in the retina is connected to the brain through the optic nerve, which passes through a hole in the choroid and sclera in the posterior of the eye. Where the optic nerve forms there are no photoreceptors, resulting in a blind spot known as the optic disk.
The human eye is an organ which reacts to light and pressure. As a sense organ, the mammalian eye allows vision. Human eyes help provide a three dimensional, moving image, normally coloured in daylight. Rod and cone cells in the retina allow conscious light perception and vision including color differentiation and the perception of depth.