Pertanyaan

Read the text and answer the question! Being able to see things around us and the beauty of the world truly is a blessing. This blessing is all thanks to our remarkable eyes. If one’s eyes function as they should, one can see images clearly, but how exactly does that happen? Light rays enter the eye through the cornea, the clear front “window” of the eye. The cornea bends the light rays in such a way that they pass freely through the pupil the opening in the center of the iris through which light enters the eye. After that, the light rays pass through the eye’s natural crystalline lens. This clear, flexible structure works like the lens in a camera, shortening and lengthening its width in order to focus light rays properly. Light rays pass through a dense, transparent gel-like substance, called the vitreous that fills the globe of the eyeball and helps the eye hold its spherical shape. In a normal eye, the light rays come to a sharp focusing point on the retina. The retina functions much like the film in a camera. It is responsible for capturing all of the light rays, processing them into light impulses through millions of tiny nerve endings, then sending these light impulses through over a million nerve fibers to the optic nerve. Finally, when the signals from nerve systems reach our brain, it gets interpreted enabling us to see images. This process may sound quite complex that it needs sometimes to happen, but that’s not true.In fact, it happens spontaneously and very quickly that you won't even realize it. How our eyes work to help us see thingsis truly remarkable. (Adapted from: www.nkcf.org ) The main topic of the text is ....