Arrector pili muscles
bundles of smooth muscle fibres, attached to the deep part of the hair follicles, passing outward alongside the sebaceous glands to the papillary layer of the corium; they act to pull the hairs erect, causing goose bumps or goose flesh (cutis anserina).
Synonym: musculi arrectores pilorum, arrectores pilorum, erector muscles of hairs.
Explore why New Zealand has such unique flora and fauna, and learn why long periods of geographical isolation. This less..
Following nine months inside the mother's womb is the birth of the baby. Know the different stages of the birthing proce..
Geological periods is a study guide that cites the different geological periods on Earth's timeline. Each has a brief ov..
Find out more about New Zealand's unique biodiversity by exploring a range of different ecosystems and the key role of s..
Autotrophs flourished, absorbing carbon and light. Soon after, primitive life forms that could assimilate oxygen thrived..
Obtaining air outside an aquatic environment required species to acquire suitable adaptations, and this was the case of ..