Final answer:
The ear differentiates between sounds of different frequencies (pitches) through the vibration of hair cells on the basilar membrane. The brain interprets the specific locations of stimulation along the membrane as different pitches.
Step-by-step explanation:
The perception of frequency is called pitch. The auditory system differentiates between sounds of different frequencies by using the hair cells in the ear. These hair cells are arranged on the basilar membrane and vibrate in different regions based on the frequency of the sound waves. The brain interprets the specific locations of stimulation along the membrane as different pitches.