Question

Which one of the following is the correct difference between rod cells and cone cells of our retina?

• A. Overall function - Rod cells: Vision in poor light, Cone cells: Colour vision and detailed vision in bright light
  
• B. Distribution - Rod cells: More concentrated in centre of retina, Cone cells: Evenly distributed all over retina
  
• C. Visual acuity - Rod cells: High, Cone cells: Low
  
• D. Visual pigment contained - Rod cells: Iodopsin, Cone cells: Rhosopsin
  

Answer 1

Answer: (A)

Overall function - Rod cells: Vision in poor light, Cone cells: Colour vision and detailed vision in bright light

The receptor cells of the eye are called photoreceptors. They are of two types: rod cells and cone cells.

Rod cells: They contain a purplish pigment called visual purple or rhodopsin. They function in dim light and at night. They produce poorly defined images.

Cone cells: They contain a pigment called visual violet or iodopsin. They function in daylight, produce detailed images and give colour vision. Cones are much more concentrated in the yellow spot region present in the centre of the retina.

Thus, the correct answer is option A.