Science

2. the opaque contractile diaphragm perforated by the pupil and forming the colored portion of the eye
6. of water
8. the sensory membrane that lines the eye, is composed of several layers including one containing the rods and cones, and functions as the immediate instrument of vision by receiving the image formed by the lens and converting it into chemical and nervous signals which reach the brain by way of the optic nerve
11. a unit of frequency equal to one cycle per second abbreviation Hz
12. the distance in the line of advance of a wave from any one point to the next point of corresponding phase
14. the small circular area at the back of the retina where the optic nerve enters the eyeball and which is devoid of rods and cones and is not sensitive to light
16. the process of absorbing something or of being absorbed

1. the contractile aperture in the iris of the eye
3. the white part of your eye
4. either of the eighth pair of cranial nerves connecting the inner ear with the brain and transmitting impulses concerned with hearing and balance
5. a sound that is a copy of another sound and that is produced when sound waves bounce off a surface
7. the membrane of the middle ear, which vibrates in response to sound waves; the tympanic membrane
9. a tube in the inner ear that make electrical signals and then sends in to the auditory nerve
10. the tubular passage of the outer ear leading to the tympanic membrane
13. the transparent part of the coat of the eyeball that covers the iris and pupil and admits light to the interior
15. something that makes vision possible