How Many Molecules Thick Are Membranes

question 2

Multiple Choice

How many molecules thick are membranes?

• A) one
• B) two
• C) infinite
• D) varying thickness, depending on structure
• E) None of the answers is correct.

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Definitions:

Blink Reflex

An involuntary blinking of the eyelids elicited by stimulation of the cornea or sudden approach of objects, serving as a protective mechanism for the eyes.

Palpebral Fissure

Space between the upper and lower eyelids.

Nasolacrimal Duct

Duct that leads from the lacrimal sac to the nasal cavity.

Ciliary Glands

Modified sweat glands located at the edge of the eyelids, responsible for lubricating the eye surface through tear production.