Laser Technician IBEC Board Exam 2025 – 400 Free Practice Questions to Pass the Exam

The correct answer, which is associated with causing goosebumps, is indeed the arrector pili. This small muscle is attached to hair follicles and is responsible for the involuntary contractions that occur when a person experiences cold temperature or emotional responses such as fear or excitement. When the arrector pili muscles contract, they pull on the hair follicles, causing the hairs to stand upright and leading to the appearance of goosebumps on the skin's surface. This reflex action is a remnant of our evolutionary past, originally serving to make our ancestors appear larger in the face of threats and to provide insulation by trapping an additional layer of air.

The sebaceous gland, while it plays a role in producing oil to keep the skin and hair moisturized, does not have a role in causing goosebumps. The hypodermis, or subcutaneous layer, primarily serves as a fat storage area and insulation but is not involved in the goosebump reflex. The pilosebaceous unit includes the hair follicle, sebaceous gland, and the arrector pili muscle but the muscle itself is specifically responsible for the goosebump phenomenon. Thus, the arrector pili is directly responsible for the physical response of goosebumps.