10. What does an arrector muscle do?

Did you know that the arrector pili muscles are tiny, smooth muscles attached to hair follicles? When they contract, they cause your hair to stand on end—think of it as nature's version of goosebumps! This reaction happens in response to cold temperatures or strong emotions like fear, making you appear larger to potential threats. These little muscles play more than a decorative role; they also help maintain body temperature. When you’re cold, the raised hairs create a layer of insulating air, trapping heat and keeping you warmer. So the next time you feel those little prickles, remember, they're working hard to keep you cozy!