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.
1.1 From Light to Sight: How does the Eye Confer Vision?(1) As the light enters the eye, it passes through the cornea, which bends and focuses the light on the lens. The pupil controls the amount of light that enters the eye. The lens then focuses the light onto the retina, forming an inverted image. The lens changes its shape to adjust the focus on both distant and near objects, a process called accommodation.