Answer:
Specialized cells and tissues within these organs receive raw stimuli and translate them into signals the nervous system can use. Nerves relay the signals to the brain, which interprets them as sight (vision), sound (hearing), smell (olfaction), taste (gustation), and touch (tactile perception).
To help the frog to maintain homeostasis
Some examples could be Giraffes with long necks and the darkening of London's peppered moths after the industrial revolution. Direct selection is the shift of the population of one species towards a certain phenotype. -reference.com
