Chapter 6.3 - Exam Review

Question 1

The (rods/cones) of the Retina are utilised for night vision or peripheral vision during the day?

Answer 1

Rods.

Question 2

The amount of light entering the eye is controlled by the (lens/iris)?

Answer 2

Iris.

Question 3

Perfect vision (6/6 or 20/20) is limited to the most central part of the Retina which contains only cones. What is this most central part of the Retina called?

Answer 3

The Fovea.

Question 4

It takes (30 seconds/30 minutes) for the eyes to adjust to sunlight and (30 seconds/30 minutes) for them to adjust to darkness?

Answer 4

• 30 seconds.

- 30 minutes.

Question 5

During daylight, because of the central location of the cones, you can see an object better by looking directly at it. To see an object more clearly at night, how is the best way to view it?

Answer 5

Slightly off-centre.

Question 6

True or False. Closing one eye if you are briefly exposed to bright light in the cockpit may protect that eye so it need not re-adapt to darkness?

Answer 6

True.

Question 7

True or False. Red light in the cockpit at night may degrade and distort some small features on maps?

Answer 7

True.

Question 8

Myopia is a refractive error of the eye. It is commonly called (Short-sightedness/long-sightedness)?

Answer 8

Short-sightedness.

Question 9

A condition where the focusing power of the eye weakens with age is called (astigmatism/presbyopia)?

Answer 9

Presbyopia.

Question 10

For the human eye to discriminate between two objects, the objects must be separated by less than (30 seconds/15 seconds) of arc?

Answer 10

30 seconds.

Question 11

Visual fatigue can lead to impaired visual focusing which is related to empty-field myopia. List four common symptoms of visual fatigue?

Answer 11

• Blurred Vision.
• Heavy Eyelid Sensation.
• Frontal Headache.
• Sore Eyes.

Question 12

To overcome the problem of a short focal distance in ‘empty’ sky condition, Pilots should repeatedly re-focus on the (closest/most distant) object that can be seen?

Answer 12

Most Distant.

Question 13

The (cones/rods) of the Retina play the major part in the perception of colour?

Answer 13

Cones.

Question 14

Most colour vision deficiencies are inherited. Which two colours are usually affected?

Answer 14

• Red.

- Green.

Question 15

If you look towards the sun for any length of time, visual efficiency gradually reduces. Briefly explain the reason for this?

Answer 15

Too much light enters the eyes.

Question 16

A ventilation passage which connects the middle ear to the back of the nose is called the (Otolith Passage/Eustachian Tube)?

Answer 16

Eustachian Tube.

Question 17

Both the Cochlea and the Vestibular Apparatus are located in the (middle/inner) ear?

Answer 17

Inner.

Question 18

The Cochlea is responsible for our (hearing/balance) and the Vestibular Apparatus for our (hearing/balance)?

Answer 18

• Hearing.

- Balance.

Question 19

The eardrum, in order to function properly, must have equal pressure on either side so that it can vibrate freely and allow us to hear. By what structure is this pressure on either side so it can vibrate freely and allow us to hear? By what structure is this pressure equalised?

Answer 19

The Eustachian Tube.

Question 20

Semi-circular canals, Otoliths, sensory hair cells, fluid and nerves, are all part of the (Hearing Mechanism/Vestibular System)?

Answer 20

Vestibular System.

Question 21

Vibrations from the eardrum are amplified in the (middle/lower) ear before sound is conducted to the inner ear?

Answer 21

Middle.

Question 22

A major component of the (middle ear/inner ear) is the Eustachian Tube?

Answer 22

Middle.

Question 23

In the (inner/middle ear), the (eardrum/cochlea) converts amplified sound vibrations into nerve impulses which are then transmitted to the brain via the Vestibulocochlear Nerve?

Answer 23

• Inner.

- Cochlea.