Why do we sweat?

One of the challenges I give my students early in the year is to describe how a molecule of water moves from the mouth to a muscle cell in the arm. The goal of this exercise is for the students to be able to demonstrate their understanding of the three fluid compartments in the body: plasma (the non-living part of the blood), interstitial fluid (the fluid that surrounds cells) and intracellular fluid (the fluid inside cells). Students can reliably get the water to the stomach, but then struggle to complete the process.

We know that fluid moves throughout our body and that some of the fluid stays in our body and some is lost through sweat, urine, feces and breathing.  The precise mechanisms by which this happens are a little tricky and exposing students to this process enables them to gain a greater understanding of how difficult it is to maintain homeostasis generally. 

One of our common experiences is that we sweat when we exercise or are in hot weather. We all know that the sweat has a cooling effect on our body and that when we are sweating, we also get thirsty. We also know that we have sweat glands and that some parts of our body have more sweat glands than other parts. What most people don't know is where the sweat comes from and what process triggers the sweat reflex. Why does your body heat up when you exercise? 

Well, this post won't answer those questions for you, but I do have a new resource that will and I wanted to tell you about it and the process by which it got made. As a science teacher, I listen to a lot of podcasts and one of my favorites is called Horizontal Transfer, hosted by David Knuffke (@davidknuffke) and Paul Andersen (@paulandersen). Paul is known for his video series on youtube (bozemanscience) which initially started out as a way for him to "flip" his AP Biology class and later morphed into covering almost every science course as well as some associated videos. He gave a TED talk a few years ago and then made a TED-Ed video on the five fingers of evolution. David served as the AP Biology teacher community moderator for the College Board and produced an excellent series of Prezi's for his class. He also wrote a video for TED-Ed on the birthday riddle. 

In one of their last podcasts, they discussed how you can get a video produced by TED-Ed. Because the quality of the animations was so good, I always assumed that these were professionally produced and that the writers were invited to write the scripts. Through their discussion, I learned that I could suggest a story idea and could then be asked to write the script. While I have some experience writing and editing for Science Screen Reports (www.ssrvideo.com) in the past, I had never submitted an original idea for a script. 

I went to the link (https://ed.ted.com/get_involved) and submitted my idea. Since it wasn't a super exciting, I wasn't expecting much. To my surprise, there was some interest and I scheduled a meeting to discuss my idea. In the meantime, I put together a script (with the TED-Ed narrator voice in my head). When I pitched my idea, they were interested more in the idea of sweat than the more general movement of fluids through the body. As a result, I reworked the script and submitted it. 

They had a writer work on it and she gave it a better opening and some other tweaks. Once we had worked it down to a more manageable story, a fact-checker came in and looked over the script and made some important contributions to the accuracy that I had glossed over. After that, we had to get the script down to the time frame they wanted to work in which was less than 4 minutes. To do that, they asked me to tweak the script and say more using fewer words. It was a real challenge, but pretty exciting as I found my writing skills were better than I thought they were. 

One of the goals of the TED-Ed program is that topics should be accessible to an instructional setting as well as the general public. When I wrote and when the story was animated, that challenge had to be kept in mind. 

Once the script was finalized, they had the audio recorded. Then they found an animator who was interested in the story and agreed to work on it. Walkir Fernandes from Dogzilla Studios (http://www.dogzilla.com.br/) did an awesome job of bringing the story to life. Once again, I was afforded the chance to make suggested changes so that the animation more accurately described the process. While I have always been impressed by the quality of the animations in TED-Ed videos, this one is well above the standard. Walkir finished the work and then submitted it to TED-Ed who added the opening and closing sequences. 

After the script was finished and the animation process started, I was asked to write the supporting work including the introduction that appears above the video and dig deeper sections. That was cool because I could write a personal note and some other sources for people to explore the topic as well as some assessment items. 

I would encourage you to consider going through the process, even if you not sure you have a good idea or are intimidated by the process. There is a lot of support along the way from some really professional  people who are passionate about doing good work. 

If you want to watch it, go to facebook and search for Constantly Curious TED-Ed or just click on this link. I'll update the blog when it is published on Youtube.