Q.7- 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?
(a) Cones are responsible for color vision. They require brighter light to function than rods require. There are three types of cones, maximally sensitive to long-wavelength, medium-wavelength, and short-wavelength light (often referred to as red, green, and blue, respectively, though the sensitivity peaks are not actually at these colors). The color seen is the combined effect of stimuli to, and responses from, these three types of cone cells.
(b) The Inner ear has three semi-circular canals forming cochlea. Cochlea is responsible for maintaining the body balance.
(c) The pupil in the eye functions like an aperture. This dilates in case of low light and constricts in case of intense light thereby regulating the amount of light falling on the retina.