cones rods

Question 1

Rods are more sensitive to light

Answer 1

● Several rods connected to a single neurone
● Spatial summation to reach / overcome
threshold to generate an action potential

Question 2

Rods give lower visual acuity

Answer 2

● Several rods connected to a single neurone
● So several rods send a single set of impulses to brain

Question 3

Rods allow monochromatic vision

Answer 3

● 1 type of rod / (containing one) pigment

Question 4

Cones are less sensitive to light

Answer 4

● Each cone connected to a single neurone
● No spatial summation

Question 5

Cones give higher visual acuity

Answer 5

● Each cone connected to a single neurone
● Cones send separate (sets of) impulses to
brain

Question 6

Cones allow colour vision

Answer 6

● 3 types of cones
○ Red-, green- and blue-sensitive
● With different optical pigments → absorb
different wavelengths
● Stimulation of different combinations /
proportions of cones gives a range of colour perception