Pretty much what the title states.
Some cells/structures in the human body undergo rejuvenation periodically by flushing away older cells and growth of new ones. E.g Skin, Blood
Does this (for want of a better word) 'rejuvenation' apply to Rods/Cones within the eye too? If so, how are the old cells flushed out - or do the old cells become part of the local humour?