Macula lutea is part of

In the human eye,the fovea is the central point of vision,where:

Answer briefly:
$(a)$ How do you perceive the colour of an object?
$(b)$ Which part of our body helps us in maintaining the body balance?
$(c)$ How does the eye regulate the amount of light that falls on the retina?

Which of the following food items is essential for the synthesis of rhodopsin?

Cones contain a photosensitive chemical known as

Rods and cones are present in