Q: How do we See Colours ?
Sol: We know that retina is a delicate membrane having enormous number of light-sensitive cells. These cells are in the shape of rods and cones. The rod shaped cells respond to the intensity of light, with different degree of brightness and darkness. In dim light only rod are sensitive cones are not. On the other hand, cones respond to colours. Cones become active in bright light only and make colour perception possible. Upto different colours perception due to different structure of rods and cones. Due to having retinal cones, bees are sensitive to ultra-violet light.