Questions		5
Questions
1.	What part of the eye bends the most light?
	a.	The cornea
	b.	The lens
	c.	The pupil
	d.	The retina	5
2.	Which part of the eye has the best visual acuity?			Questions
	a.	The retina
	b.	The fovea
	c.	The lens
	d.	The cornea
3.	The resolving power of the fovea decreases rapidly at only ..................... from its
	centre.
	a.	5°
	b.	13° to 16°
	c.	3°
	d.	2° to 3°
4.	What is “empty field myopia”?
	a.	It is a term used when the eye, if it has nothing on which to focus will tend to
		focus at infinity
	b.	It is a term used when the eye, if it has nothing on which to focus will tend to
		focus between 4 to 6 metres
	c.	It is a term used when the eye, if it has nothing on which to focus will tend to
		focus between 10 to 12 metres
	d.	It is a term used when the eye, if it has nothing on which to focus will tend to
		focus between just under 1 to 1.5 metres
5.	What causes long or short sightedness?
	a.	Presbyopia
	b.	Astigmatism
	c.	Distortion of the eyeball
	d.	Distortion of the cornea
6.	Is a pilot allowed to fly wearing bifocal contact lenses?
	a.	Yes
	b.	Yes, if cleared to do so by a qualified aviation specialist
	c.	Yes, if cleared to do so by the authority
	d.	No
7.	What part of the spectrum should sunglasses filter out?
	a.	The red and UV end of the spectrum
	b.	The blue and UV end of the spectrum
	c.	All high intensity light
	d.	UV only

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5 Questions

Questions 5

8.What four factors affect night vision?

a.Age, alcohol, altitude and smoking

b.Age, altitude, instrument lights and smoking

c.Instrument lights, alcohol, altitude and smoking

d.Age, alcohol, altitude and instrument lights

9.Cones detect .................... and are mostly concentrated at the .....................

a.	black and white	fovea
b.	colour	fovea
c.	black and white	retina
d.	colour	entry point

10.What is the recommended course of action if encountering an electrical storm during flight?

a.Pull the visors down

b.Turn the cockpit lights down

c.Turn the cockpit lights to full

d.Put on sunglasses if available

11.Where is the “blind spot”?

a.On the iris

b.On the fovea

c.On the edge of the lens

d.At the entrance to the optic nerve

12.Peripheral vision is looked after by the:

a.rods

b.cones

c.rods and cones

d.fovea

13.Does lack of oxygen affect sight?

a.Yes

b.No

c.Sometimes

d.It depends on the health of the individual

14.The amount of light allowed to enter the eye is controlled by the:

a.cornea

b.retina

c.iris

d.fovea

15.Accommodation is controlled by the:

a.ciliary muscles

b.iris

c.lens

d.cornea

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Questions 5

16.The maximum number of rods are found ..................... from the fovea.

a.10°

b.20°

c.15°

d.30°

17.Dark adaption takes about ..................... for the rods and .................... for the cones.

a.	30 minutes	7 minutes
b.	7 minutes	30 minutes
c.	15 minutes	20 minutes
d.	25 minutes	45 minutes

18.Stereopsis is associated with:

a.night flying

b.depth perception

c.acuity

d.colour blindness

19.Hypermetropia is caused by a ...................... eyeball and is corrected by a

.................... lens.

a.	elongated	convex
b.	shortened	concave
c.	shortened	convex
d.	elongated	concave

20.Astigmatism is normally associated with the:

a.retina

b.fovea

c.iris

d.cornea

21.Glaucoma is caused by:

a.an increase in the pressure of the eye

b.a decrease in the pressure of the eye

c.a defect of the cornea

d.a defect of the retina.

22.Cataracts are associated with the:

a.retina

b.tear ducts

c.iris

d.lens

23.Does colour blindness affect acuity?

a.Yes

b.No

Questions 5

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5 Answers

Answers

Answers 5

1	2	3	4	5	6	7	8	9	10	11	12
a	b	a	d	c	d	b	a	b	c	d	a
13	14	15	16	17	18	19	20	21	22	23
a	c	a	a	a	b	c	d	a	d	b

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