hair follicles
The arrector pili and epidermis are related only in that the action of the arrector pili causes "goosebumps" to form at the epidermis.
arrector pili.
Whilst all of these things are within the dermis of the skin, the arrector pili is the odd thing out. The arrector pili is a muscle where as the rest (meissner, pacinian and merkel) are nerve endings. The result of contraction of arrector pili is the standing up of a hair. The meissner corpuscle is a sensory nerve ending that is specific for fine touch, as are merkel cells [light touch]. The pacinian corpuscle is a nerve ending specific for sensation of deep pressure and vibration.
arrector pili muscle cell
Arrector pili is the muscle the raises hair. This is taught in health class.
The contraction or relaxation of the erector pili muscle determines the orientation of hair on the skin. When it contracts, due to fear or cold, hair stands upright.This is a tiny muscle that attaches to the base of a hair follicle mammals at one end and to dermal tissue on the other end.
involuntary
arrector pili
Goosebumps are caused by little muscles called the arrectores pilorum (the hair erector muscles). Contraction of these muscles elevates the hair follicles above the rest of the skin. And it is these tiny elevations we perceive as goose bumps. Source: http://www.medicinenet.com/script/main/art.asp?articlekey=6842
arrector pili
Within the hair follicles.
An arrector pili is any of a group of small muscles attached to hair follicles in mammals, the contraction of which causes the hairs to stand on end.