Lecture 3 - Visible Light and the Eye

Question 1

What is visible light?

Answer 1

A specific band of energy within the electromagnetic energy spectrum.

Question 2

What is electromagnetic energy?

Answer 2

Energy that is produced by electric charges and is radiated in waves.

Question 3

How is electromagnetic energy measured?

Answer 3

Wavelength - distance between the peaks

Question 4

What does visible light range from?

Answer 4

400-700 nanometres.

Question 5

Label the areas of the eye

Answer 5

Question 6

What is the cornea?

Answer 6

The transparent tissue at the very front of the eye.

Question 7

What is the sclera?

Answer 7

Tough white tissue that coats the rest of the eye

Question 8

What is the iris?

Answer 8

Muscle tissue that controls the size of the pupil and, thereby, the amount of light that enters the eye.

Question 9

What do the ciliary muscles do?

Answer 9

Increase focusing power of lens by increasing is curvature

Question 10

What is presbyopia?

Answer 10

Hardening of the lens and weakening of ciliary muscles causes the distance of a near point to increase with age.

Question 11

What is hyperopia?

Answer 11

Farsightedness

Question 12

What is refractive myopia?

Answer 12

Cornea or lens bends too much light

Question 13

What is axial myopia?

Answer 13

Eyeball is too long

Question 14

What do the outer segments of rods and cones do?

Answer 14

• Contain light sensitive visual pigment
• This is where light is transduced into electricity

Question 15

What do the inner segments of rods and cones do?

Answer 15

Houses important cellular structures including ribosomes and mitochondria

Question 16

What does the synaptic terminal of rods and cones do?

Answer 16

Electric signal propagates here and is passed onto visual neurons

Question 17

What is isomerisation?

Answer 17

The process in which retinal changes its shape due to the absorption of light.