Our Eyes

15 Points Per Correct Answer - No time limit  

1. While talking about the human eye, what is the "pupil"? A light-sensitive screen A hole of variable size A viscous fluid One of the unfortunate victims of the System

2. The eye is very sensitive to bright light, while at the same time, it isn't very easy to see things in insufficient light. And so it is necessary to control the amount of light entering the eye through the pupil- it should be just about enough to see things clearly, but not so much as to damage the eye. What is the assembly of smooth (unstriated) muscle which controls the amount of light entering the eye called? Retina Gizzard Cornea Iris

3. What is the scientific term for the "white of the eye", the part surrounding the eyeball? Sclera Albumen Conjunctiva Epiglottis

4. Which part of the eye is analogous to the photographic plates which were once used (and still are, but to a lesser extent) in cameras? Answer: (Six letters; take a look at the next few questions)

5. The choroid is composed primarily of blood vessels. True False

6. What is the thick, transparent fluid that comprises about 2/3rd of the eye's volume? Protoplasm Tears Iris Vitreous

7. What are the two types of light-sensitive cells which are contained in the retina? Pyramids and cubes Rods and cones Dodecahedrons and double helices Spheres and oblate spheroids

8. What wavelengths of light can be detected by the human eye? 400 - 700 metres 400 - 700 nanometres 400 - 700 millimetres 400 - 700 micrometres

9. While the so-called "fine adjustment" for the formation of a clear image on the retina is done by the crystalline lens, it is not, by itself, capable of refracting the incident light to the degree required. Which part of the eye fulfills the function of the "coarse adjustment"? Iris Glomerulus Pupil Cornea

10. The focal-length of the ___ is controlled by the ciliary muscles. Cornea Sclera Aqueous humour Eye-lens

11. What is the "blind spot" of the eye? A small area of the retina where the optic nerve enters the eye A hazy or opaque region on the eye-lens, where a cataract has begun developing A part of the cornea which has been damaged A region of the eye into which the extra-ocular muscles protrude

12. The extra-ocular muscles (EOMs) are responsible for the movements of the eye. How many of these are present in (or rather, outside) each eye? 6 4 3 7

13. What do the Meibomian glands lining the edge of the eyelid, the lachrymal glands, and the goblet cells in the conjunctiva collectively produce? Answer: (One word; four or five letters; secreted while chopping onions or in times of sorrow)

14. For how much time does the impression or the sensation of an image remain on the retina of the eye? About 3 seconds About 1/16th of a second Till you blink next Till you go to sleep and wake up again

15. Even though this quiz is titled "Our EYES", all the questions preceding this one have focused entirely of the structure and functioning of just an individual eye by itself. Besides an increased field of vision, what is the other important advantage of possessing two, and not one, eye(s)? Seeing gamma rays Perception of size Perception of depth (radial distance) Seeing in infrared (and at other low-energy frequencies)