What is the function of the Piloerector muscle?

What is the function of the Piloerector muscle?

The piloerector (arrector pili) muscles, which cause skin hair to stand up (goose pumps); and the irises, which control the diameter of the pupils in the eyes, are example of smooth muscle structures[1–5].

What are Piloerector muscles?

The arrector pili muscles, also known as hair erector muscles, are small muscles attached to hair follicles in mammals. Contraction of these muscles causes the hairs to stand on end, known colloquially as goose bumps (piloerection).

What is erector Pilorum?

Arrectores pilorum: Tiny muscles that act as the hair erector muscles. The nerve discharge causes contraction of 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.

What is the Arrector pili muscle composed of?

The arrector pili muscle (APM) consists of a small band of smooth muscle that connects the hair follicle to the connective tissue of the basement membrane. The APM mediates thermoregulation by contracting to increase air-trapping, but was thought to be vestigial in humans.

How deep under the skin are hair follicles?

A good scalp biopsy should include terminal hair bulbs and usually is 0.8 to 1cm deep. Article Transverse microscopic anatomy of the human scalp.

What are the 3 nerves found in the skin?


  • Meissner receptors detect light touch.
  • Pacinian corpuscles perceive deep pressure and vibrational changes.
  • Ruffini endings detect deep pressure and stretching of the skin’s collagen fibers.
  • Free nerve endings located in the epidermis respond to pain, light touch, and temperature variations.

What is the hair follicle made up of?

The hair follicle is made of multiple layers of cells that form from basal cells in the hair matrix and the hair root. Cells of the hair matrix divide and differentiate to form the layers of the hair. Watch this video to learn more about hair follicles.

What is the role of the arrector pili muscle in human thermoregulation?

Arrector Pili Muscles The hairs on the skin lie flat and prevent heat from being trapped by the layer of still air between the hairs. When these muscles relax their attached hair follicles are not erect. These flat hairs increase the flow of air next to the skin and increase heat loss by convection.

Where are dermal papillae found and what is their purpose?

You should notice that the dermis extends up into the epidermis in structures called dermal papillae. These have two functions. First, they help adhesion between the dermal and epidermal layers. Second, in areas of thick skin like this, they provide a large surface area, to nourish the epidermal layer.

What is the function of the epidermal ridges and the dermal papillae?

What is the function of the epidermal ridges and dermal papillae? Epidermal ridges and dermal papillae provide increased surface area for the epidermis and dermis to connect.

Can I regrow hair follicles?

Hair regrowth If you have conditions like alopecia or balding, you might wonder if it’s possible to stimulate a hair follicle to regrow hair. If a follicle has been damaged, it’s not possible to restimulate it.

What does the arrector pili muscle do?

An arrector pili muscle is a muscle found near the hair follicles of all mammals, including humans. It is the muscle responsible for making hairs “stand on end.”.

Is the arrector pili muscle voluntary or involuntary?

Arrector pili muscles are a type of smooth muscle. Unlike the skeletal muscles that direct human movement, for example, smooth muscle is not under conscious or voluntary control. Other examples of smooth muscle can be found in the stomach and intestines, which work unconsciously to process and pass food through the digestive tract.

What does piloerector mean?

Piloerector meaning A muscle responsible for piloerection.

Where are the arrector pili muscles located?

Arrector pili muscles are the tiny muscles between individual hair follicles and an adjacent region of the outer-part of the dermis layer of the skin. The arrector pili muscle associated with each hair follicle extends from the side of the hair follicle to the outermost (i.e. towards the surface of the skin) part of the dermis layer of the skin.