As hair cells form in follicles, they push other cells out of the follicle. Check out this HowStuffWorks podcast to learn more about your hair's growth and rest phases.
Learn more about your ad-choices at https://www.iheartpodcastnetwork.com
See omnystudio.com/listener for privacy information.
Episode Transcript
Streaming TV shows and movies directly to your home is
a breeze with Netflix. As a Netflix member, you can
instantly watch TV and movies on your PC, Mac, mobile device,
or television. Get a free thirty day trial membership. Go
to Netflix dot com slash stuff and sign up today.
Welcome to brain Stuff from how Stuff works dot com
where smart happens. Hi. I'm Marshall Brain with today's question.
(00:30):
Why does the hair on your arms stay short while
the hair on your head can grow very long? Each
hair on your body grows from its own individual hair follicle.
Inside the follicle, new hair cells form at the root
of the hair shaft. As the cells form, they push
older cells out of the follicle. As they're pushed out,
(00:52):
the cells die and they become the hair that we see.
A follicle will produce new cells for a certain period
of time, depending on where it's located on your body.
This period is called the growth phase for the hair.
Then it will stop growing for a period of time
This is called the rest phase, and then start the
growth phase again. When a hair follicle enters the rest phase,
(01:14):
the hair shaft breaks off, so the existing hair falls
out and a new hair takes its place. Therefore, the
length of time that a hair is able to spend
growing during the growth phase controls the maximum length of
that hair. The cells that make the hairs on your
arms are programmed to stop growing every couple of months,
so the hair on your arms stays short. The hair
(01:36):
follicles on your head, on the other hand, are programmed
to let the hair grow for years at a time,
so the hair can grow very long. Animals that shed
have hair follicles that synchronize their rest phase, so all
the follicles enter the rest phase at once. This way,
all the hair falls out at the same time. A
dog that sheds will lose its hair in large clumps.
(01:59):
Some animals can also switch the coloring agent in the
hair follicle audit off, so in the summer of the
hair is pigmented brown with melanin, but in the winter
it's not pigmented, leaving the hair white. For more on
this and thousands of other topics, because it how staff
works dot com. Audible dot com is the leading provider
(02:21):
of downloadable digital audio books and spoken word entertainment. Audible
has over one hundred thousand titles to choose from to
be downloaded to your iPod or MP three player. Go
to audible podcast dot com slash brain stuff to get
a free audio book download of your choice when you
sign up today
BrainStuff News
Host
Lauren Vogelbaum
Popular Podcasts
On Purpose with Jay Shetty
I’m Jay Shetty host of On Purpose the worlds #1 Mental Health podcast and I’m so grateful you found us. I started this podcast 5 years ago to invite you into conversations and workshops that are designed to help make you happier, healthier and more healed. I believe that when you (yes you) feel seen, heard and understood you’re able to deal with relationship struggles, work challenges and life’s ups and downs with more ease and grace. I interview experts, celebrities, thought leaders and athletes so that we can grow our mindset, build better habits and uncover a side of them we’ve never seen before. New episodes every Monday and Friday. Your support means the world to me and I don’t take it for granted — click the follow button and leave a review to help us spread the love with On Purpose. I can’t wait for you to listen to your first or 500th episode!
Ruthie's Table 4
For more than 30 years The River Cafe in London, has been the home-from-home of artists, architects, designers, actors, collectors, writers, activists, and politicians. Michael Caine, Glenn Close, JJ Abrams, Steve McQueen, Victoria and David Beckham, and Lily Allen, are just some of the people who love to call The River Cafe home. On River Cafe Table 4, Rogers sits down with her customers—who have become friends—to talk about food memories. Table 4 explores how food impacts every aspect of our lives. “Foods is politics, food is cultural, food is how you express love, food is about your heritage, it defines who you and who you want to be,” says Rogers. Each week, Rogers invites her guest to reminisce about family suppers and first dates, what they cook, how they eat when performing, the restaurants they choose, and what food they seek when they need comfort. And to punctuate each episode of Table 4, guests such as Ralph Fiennes, Emily Blunt, and Alfonso Cuarón, read their favourite recipe from one of the best-selling River Cafe cookbooks. Table 4 itself, is situated near The River Cafe’s open kitchen, close to the bright pink wood-fired oven and next to the glossy yellow pass, where Ruthie oversees the restaurant. You are invited to take a seat at this intimate table and join the conversation. For more information, recipes, and ingredients, go to https://shoptherivercafe.co.uk/ Web: https://rivercafe.co.uk/ Instagram: www.instagram.com/therivercafelondon/ Facebook: https://en-gb.facebook.com/therivercafelondon/ For more podcasts from iHeartRadio, visit the iheartradio app, apple podcasts, or wherever you listen to your favorite shows. Learn more about your ad-choices at https://www.iheartpodcastnetwork.com
The Joe Rogan Experience
The official podcast of comedian Joe Rogan.