Goosebumps are a strange phenomenon in humans. What causes those little bumps to appear when you are cold or frightened?
The answer lies in the anatomy of the skin. Students, read descriptions of structures found in the epidermis, dermis, and hypodermis. Then, they use those descriptions to label a model of the skin. The model also shows hair follicles, sweat glands, and Pacinian corpuscles.
They note that a tiny muscles attaches to the hair shaft – the arrector pili muscle. When this muscle contracts, the hair stands up. The contraction also causes a small bump to raise on the skin’s surface, a goosebump!
On the second page of the document, students closely examine how the arrector pili muscle interacts with the hair and epidermis. They use the image to briefly describe what is happening. Next, they focus on the oil glands and how it relates to acne. Finally, they suggest an evolutionary reason for the behavior. In animals, hair standing up can make them appear larger or more intimidating. Raising of the hair can also provide insulation from the cold.
A link to the video from the Institute of Human Anatomy explains in more detail how the phenomenon works. The video also shows a section of real human skin to highlight the dermis and epidermis. The video is 10 minutes long, but I usually only play the first 5 minutes. The last part of the video explores the role of the hypothalamus and autonomic nervous system.
I also have several skin models for display. Many were inherited from the previous anatomy teacher, though you can purchase models from supply companies or Amazon.
I do not spend a lot of time on skin, but it does make an appearance in the chapter on Tissues. Then we revisit skin when we study the senses in the second semester. My entire anatomy and physiology curriculum is posted on Google Docs. This includes links to lessons, slides, and labs that we do in my anatomy class.
Tests are available for purchase from Teachers Pay Teachers with answer keys for most of the worksheets I assign in class.