Which one of the following is the correct difference between rod...

The retina is the neural and sensory layer of eyeball. A small, oval, yellowish area of the retina lying exactly opposite the centre of cornea is named the macula lutea or yellow spot, which has at its middle a shallow depression the fovea centralis. The fovea centralis has cone cells only. It is devoid of rods and blood vessels. The rods contain the rhodopsin (visual purple) pigment and enable the animals to see in darkness. Therefore, present in large number in nocturnal animals. The cones contain the iodopsin (visual violet) pigment and chiefly concerned with distinction in colour and light vision during day time.