what is called the opening and shutting of a eyelid
Answers
Answer:
Closure is characterised by a progressive narrowing of the palpebral fissure, in a zipper-like fashion, from the outer canthus to the inner canthus. This moving wave of closure serves to force aqueous in the inter-palpebral fissure toward the lacrimal puncta, thus aiding tear drainage.
Levator Apparatus :The levator palpebrae superioris and superior tarsal muscles both act to open the eyelid. They are only present in the upper eyelid. Originates from the lesser wing of sphenoid, and inserts into the upper eyelid and the superior tarsal plate.
Explanation:
The main muscles, in the upper eyelid, that control the opening and closing are the orbicularis oculi and levator palpebrae superioris muscle. The orbicularis oculi closes the eye, while the contraction of the levator palpebrae muscle opens the eye.
Answer:
Orbicularis oculi