Final answer:
A melody uses tones from a scale, which is a sequence of notes within an octave. Musical notes, used to compose melodies, result in unique sounds when combined with various frequencies and intensities, characteristic to different instruments and voices.
Step-by-step explanation:
A melody is built on tones or pitches selected from an ascending or descending pattern of pitches, within an octave called a scale. Musical notes are the basic units of music with specific names, such as A, B, C, and so on, and these notes are combined to create tunes and melodies. The number and relative intensity of multiple frequencies, including the fundamental and overtones, dictate the unique sound characteristics of musical instruments and voices. For example, the way the note middle C sounds on a trumpet is very different from how it sounds on a clarinet due to the different combinations and intensities of overtones each instrument produces.