Eyes

Eyes are the organs of vision in the human body, functioning by detecting light and converting it into electrochemical impulses carried by neurons to the brain. Structurally, the eye is a complex optical system, which includes the cornea, lens, retina, iris, and optic nerve among other components. The cornea and lens focus light onto the retina, where photoreceptor cells (rods and cones) detect varying light intensities and colors. Rods are more sensitive to light and are primarily involved with vision in dim lighting, while cones function in brighter light and enable the perception of color.

The intricate process of vision begins when light enters the eye through the cornea, then passes through the aqueous humor, continues through the pupil (the size of which is regulated by the iris to control the amount of light entering), and then through the lens, which fine-tunes focus. This focused image then hits the retina, initiating a cascade of biochemical and electrical events that result in visual signals being sent to the brain via the optic nerve. Here, the brain interprets these signals, allowing us to understand our visual surroundings. The eyes also possess protective mechanisms, including the eyelids, eyelashes, and tear system, which help to shield them from foreign particles and maintain the ocular surface's health.