szemhéjban

Szemhéjban is a Hungarian word that translates to "eyelid" in English. It refers to the fold of skin that covers and protects the eye. Humans and many other animals have eyelids, which serve several important functions.

The primary function of eyelids is to protect the eye from foreign objects such as dust, debris, and insects. When an object comes near the eye, the eyelids close reflexively, preventing injury. Eyelids also help to keep the eye moist. Blinking, the rapid opening and closing of the eyelids, spreads tears across the surface of the eye. Tears lubricate the eye, wash away irritants, and contain antibodies that fight infection.

The eyelids also play a role in vision. By opening and closing, they can regulate the amount of light that enters the eye, similar to how a camera aperture works. In bright light, the eyelids can partially close to reduce glare, and in dim light, they can open wider to allow more light in.

The eyelid is composed of several layers, including skin, muscle, and connective tissue. The muscles within the eyelid allow for blinking and for holding the eyelid open. The inner surface of the eyelid is lined with a thin membrane called the conjunctiva, which also covers the white part of the eye. Conditions affecting the eyelids can range from minor irritations like styes and chalazia to more serious issues such as blepharitis and ptosis.