Quiz

2. The eardrum is a delicate membrane that vibrates as sound passes through it and the vibrations pass on to the middle ear. Do you know the other name for the eardrum?

3. The middle ear contains a tube that helps to equalise pressure and drain mucus, can you name it?

4. There are three small bones in the middle ear, malleus, incus and stapes. What is their collective name?

5. What is the scientific name for the white area of the eyeball surrounding the coloured one?

6. What is the length of light, also known as the visible range that can be detected by the human eye?

7. For how much time does the impression of an image remain on the retina of the eye?

8. The movement of the eye is controlled by which muscles?

— Rehan Jalal

ANSWERS

1. Pinna or auricle. Its function is to collect sound which is then passed through to the middle ear. 2. Tympanic membrane 3. The Eustachian tube 4. Ossicles, these small bones help carry sound from the eardrum, through the middle ear and into the inner ear. 5. Sclera, it is thinner and less opaque in children and as people grow older, it becomes more yellowish. 6. Between 400 to 700 nanometres. One nanometre is one-billionth of a metre. Beyond 700nm is infrared radiation and below 400 nm is the ultra-violet (UV) radiation. 7. Around 1/16th of a second. 8. The extra-ocular muscles. There are seven of them — four are responsible for controlling the eye’s movements from left to right and from top to bottom, and vice versa, two move the eye inward or outward and the last one controls the eyelid. All these muscles control the eye movement in unison.