to protect frm foreign bodies
By covering the eyeball.
If you squish your eyeball, tears and blood will come out.
Yes, when the eyelids are closed, they cover the entire eyeball including the posterior portion. This helps protect the eye from external elements such as dust and debris.
no they dont have eyelids
Tears come from the lachrymal glands, located under your upper eyelids.
Yes, the conjunctiva is a thin, transparent mucous membrane that lines the inner surface of the eyelids and covers the white part of the eyeball. It helps protect and lubricate the eye.
The eyelids of all snakes are non-existent ! Instead, they have a clear scale (the 'brille') which covers the eyeball. Each time a snake sheds, this covering is replaced.
Whales and sharks dont have eyelids because instead they metmorphisize
Adnexa of the Eyes
Yes, the eyeball itself does not have any feeling as it lacks pain receptors. However, the surrounding tissues and structures of the eye, such as the eyelids and cornea, can feel sensations like touch and irritation.
Orbital exenteration refers to the removal of the entire eyeball, orbital soft tissues, and some or all of the eyelids.
My doctor measured my eyes with a special instrument that fits around the eyelids. It is simple and perfectly comfortable.