The arrector pili muscles are in the hair follicles. When contracted, they cause the hair to stand on ends, commonly known as goosebumps.
arrector pili.
The arrector pili muscles makes the hairs on your arm stand on end.
The Arrector Pili muscle
erector pili
arrector pili
arrector pili muscle
the arector pili muscle.
arrector pili
erector pili
Arrector Pili Muscle
arrector pili muscle cell
Arrector pili is the muscle the raises hair. This is taught in health class.