Mention, where in living organisms are the following located and state their main functions :
(a) Fovea centralis (b) Organ of Corti

(a) Fovea centralis is located at the back of the eye almost at the centre of the eyeball. It is the region of the brightest vision and also of the colour vision.
(b) Organ of corti is located in the inner ear. It contains sensory cells which process hearing.