Conrad's Classroom: The Skin We're In
I’ve conducted hundreds of writing workshops over the years with students and adults of all ages. Young or older, students all have questions about the writing process. One of the first questions asked in every session is: Where do you get your ideas?
My answer is always the same. Ideas are everywhere. You just need to open your eyes and look around; open your ears and listen. It works for me.
My annual visit to the dermatologist was the spark for this month’s column. Sitting in the exam room got me thinking about just how amazing human skin is as a protective covering. It’s tough, yet flexible. It keeps harmful irritants out, but is porous enough to let off excess body heat and moisture in the form of sweat.
If cut or scraped or roughed up, skin has the ability to heal quickly, often in just a matter of days. These facts I knew already. But with curiosity piqued, I asked some questions to learn more.
Skin is actually the largest organ of the human body. Most people know a bit about human organs. The heart pumps blood through a miles-long network of arteries, veins, and capillaries. With every breath, our lungs take in oxygen from the air and expel carbon dioxide and water as waste products. Our liver and kidneys rid the body of harmful toxins.
All of those organs are connected inside our body. On the outside, our skin is the perfect covering for everything. That includes all of our organs, muscles, bones, nerves and brain.
An average-sized person has between 16 and 22 square feet of skin. Spread across a flat surface, that is enough to cover a single bed. Or, consider that a standard doorway opening is about 21 square feet. All of that skin weighs between 9 and 11 pounds. Skin accounts for about for 15 percent of our total body weight.
Our skin is the body’s protective barrier against the outside world. It’s not as tough as a turtle’s shell or a suit of armor. Still, it protects our bones, muscles, and internal organs from disease. Our skin is filled with nerve endings, the sensors that allow us to feel and touch and react to heat and cold.
Human skin is made of three separate layers and each layer has a specific purpose. The outside layer is called the epidermis. It is thickest on the palms of our hands and soles of our feet. It is thinnest on our eyelids. The epidermis also contains the pigments that give our skin its color.
The middle layer is called dermis. It contains billions of nerve endings and is home to blood vessels and the roots of every bit of hair.
The subcutaneous layer is the deepest layer of our skin. It contains fat cells. It serves as a shock absorber to help protect our internal organs.
According to scientists, our skin is constantly changing and produces new skin cells as dead cells are shed. We shed between 30,000 and 40,000 dead skin cells every minute!
Our skin totally renews itself about once every 28 to 35 days. Consider it this way: By the time you reach age 20, you’ve already cycled through a new covering of skin almost 200 times.
We need to be aware of and take care of our skin each and every day. It’s our perfect covering.
Facts to get under your skin:
Your skin is home to billions of bacteria. More than a 1,000 different kinds.
Much of the dust in your home is actually made of dead skin cells.
Damaged skin heals itself by forming a scar. Scar tissue does not have hair follicles or sweat glands.
Tough, thick skin often forms over an area that experiences repeated pressure or friction. This tough, thick patch of skin is called a callus.
Resources to learn more:
Books:
My Amazing Skin Can Heal: A Book about Boo-Boos, Bandages and Band Aids by A. D. Largie
Skin: The Largest Organ in the Body by Baby Professor
Websites:
Science Kids – Human Body Facts
How Stuff Works – How Your Skin Works
The award-winning author and editor of more than 50 science and nature books for children and young adults, Conrad J. Storad expertly draws young readers into his imaginative and entertaining “classroom” to help them better understand and appreciate the natural world. (photo by Linda F. Radke)