Speaking of Feedback Loops

Teaching kids about feedback loops? First it’s important to establish that positive feedback loops aren’t necessarily a good thing and negative feedback loops likely are not something bad!

Examples of feedback loops in the human body let kids feel more connection with the whole idea. So… negative feedback loops function to move systems back in the direction of stability and maintain homeostasis. For example, shivering when the body is cold will cause friction and heat that will raise the body temperature. In this negative feedback loop the processes involved will bring the body’s parameters back to a normal level.

In a positive feedback loop, on the other hand, processes will be engaged that will accelerate and intensify the divergence from the norm. An excellent example is seen with labor and delivery, in which it is desirable to bring the process to its conclusion quickly and efficiently. (Ask any woman whether she’d like to have a short labor or a protracted one!!) So when labor begins, instead of contractions being damped and decreasing, they increase in strength and frequency till the baby is finally delivered. This is a positive feedback loop, a process that intensifies and increases over time until the culmination is reached.

A positive feedback loop


Jump Start Their Learning–Get ‘Em Moving!

In the midst of your well-planned and entertaining lecture, you look out across the room, and suddenly it hits you. The glazed expressions, the politely stifled yawns, the drooping eyelids. Sluggish, sleepy brains can’t take in even the most vibrant and cleverly delivered lectures! What now? Get them up! Get them moving! Get the blood flowing to their brains again! This is NOT wasted time. This is an essential aid to learning!

There is plenty of information floating around now telling us what science has found: movement helps the brain form those neural pathways. Exercise helps kids learn! Breaks every 20 minutes or so, to move around, to stretch, to promote circulation, all will help to wake them up and improve their concentration. Enlist students to lead stretching exercises. And incorporating movement into the learning itself will improve comprehension and retention. It gives you a break too, and there’s nothing wrong with that!

This week we’re focusing on protein synthesis. It’s a tricky business that confuses biology students. How can movement help? Have them move around pictures to enact the process (see our Protein Synthesis Board Kit and Desk Kit), and after they’ve done that, let them work in small groups to create a skit showing the process. They won’t be “lost in translation” anymore!

The First Alchemist?

Who was the woman some call the first alchemist? Her name was Mary the Jewess or Mariam the Hebrew. She lived sometime between the first and third centuries. Why should we care? Some of the devices she created for use in chemistry procedures are still in use today, almost 2000 years later!

The double-boiler or bain-marie (Marie’s bath) is used when gentle heating is needed, whether for cooking or for carefully heating chemicals in a laboratory. And Mary’s distillation apparatus is still in use today for distilling water and more potent substances too.

Though she’s called the first alchemist, no records have been discovered showing that she was interested in the secret to eternal life, finding the philosopher’s stone, or transmutation of lead into gold. But it does appear that she was quite interested in chemical processes.

She also purportedly left behind a series of quotes that even found their way into the writings of Carl Jung!

“Join the male and the female, and you will find what is sought.”

“One becomes two, two becomes three, and out of the third comes the one as the fourth.” Very cryptic!

Downloadable Kits

So what’s the plan here?

Speak Easies is switching to a very affordable downloadable format!  Those magnetic Board Kits and Desk Kits you’ve loved will sell out and not be reprinted.  But all of those great materials will, over time, be loaded onto our website so you can download them and print them in whatever way you like:  on magnetic sheets or print and laminate to use again and again.  Or you can print them to give a set to each student for study and review and finally to glue into the lab notebook with notes!

And here’s a big plus:  we’re adding extra materials to each kit, things like worksheets, mix and match activities, more background information, and pro tips.  But there’s even more!  We’re adding new kits, for example a Do It Yourself Carbon Cycle, Dive into the Kelp Forest (food web to assemble, information on upwelling, a simulated dive), Shovel-Ready (tool safety and workplace behaviors for kids involved in outdoor projects), and much more to come!  We welcome your suggestions!  Let us hear from you!

You can purchase five downloadable kits right now here on our website, www.speakeasies.biz, or go to our store, Speak Easies Active Learning Tools for Biology, on Teachers Pay Teachers.

 

Don’t Forget Your Tick Check!

Poster available in the “Shovel-Ready” lesson on this site or at Speak Easies Active Learning Tools for Biology on Teachers Pay Teachers

Do you take your class outside to work in the school garden or restore habitat?  If you live in tick country, it pays to remind your students to check themselves for ticks at the end of the day.  Because ticks inject kininases, very effective anaesthetic substances, as they bite, a tick bite can go unnoticed for many hours–even when they’ve burrowed in to your skin!  They’re pretty easy to remove in the first few hours, and it takes 24 hours or more of the tick embedded in your skin for the pathogen that transmits lyme disease to be transmitted.  So do that tick check at day’s end.

Device for removing ticks easily. Keep it on your key chain.

 

Shovel Ready–Preparing Students for Outdoor Work

If you take your students outside to plant in the school garden or restore habitat, you know that it can be very beneficial for kids. Even the problem kid might excel at this work! But you also know that, just as when you go to the lab, it takes some preparation to ensure a safe, successful experience. Speak Easies has designed some cartoon worksheets that can make this potentially boring topic fun. Besides the one pictured here, there is “Name That Tool” and “Don’t Forget Your Tick Check”. These are available now on Teachers Pay Teachers at Speak Easies Active Learning Tools for Biology and will soon be on our website, www.speakeasies.biz, under the title “Shovel-Ready!”

What else can help make the outdoor work rewarding? Remind kids about wearing old clothes, in layers, getting a good night’s sleep the night before, and eating a hearty breakfast. Shoes can be an issue; they should be sturdy, with closed toes, and older shoes are preferable. Students should also bring drinking water and a snack if these are not provided. Also helpful to show them: “Before” and “After” pictures of habitat or the school garden.

Working in small groups can also help to make the job more fun!

Sequestering Carbon the Natural Way–in the Soil

Could plants help to trap carbon in the soil?

What do you think is the main reservoir of carbon in the biosphere?  The atmosphere, right?  Well, no.  The main reservoir is the soil, holding approximately five times as much carbon as the atmophere!  Too bad there’s not a way to sink carbon into the soil and trap it there, decreasing the carbon in the atmosphere.  But guess what!  There is!

When plants grow and produce sugars in photosynthesis, the sugars remaining after the plant uses what it needs are transported down the stem to the roots to be stored there.  But some of the sugary liquid oozes out into the soil immediately surrounding the roots.  There it feeds the microbial partners of the plant, such as mycorrhizal fungi that help provide water and nutrients for the plant.  (Talk about a nice symbiotic relationship!)

But some of those sugars stick to clumps of mineral particles in the soil, forming soil aggregates.  Here’s the amazing thing:  those aggregates can last for hundreds of years if undisturbed, and all the while they are trapping carbon because sugars are built on a backbone of carbon.  Carbon trapped for hundreds of years in the soil –out of the atmosphere!

So plant some plants, especially native perennial grasses, because they have extremely long and extensive root systems to exude that oozing syrupy sugar.  And support restorations that are planting in your area because it’s the “carbon smart” thing to do!

In Search of Intelligent Life

This NASA photo shows a radio telescope listening for communication from space.

Hello, Earth to …?  Is anyone out there in the blog world?  Anyone?  If you are reading this, give us an indication!  Should we stop trying to communicate now?  Is there intelligent life out there?  Is there intelligent life here on this blog?  Are we aiming towards empty space?  Can you send up a flare, or better yet, make a comment?  We’re getting lonely out there!

The DIY Carbon Cycle and The Trouble with Methane

Methane (CH4) and carbon dioxide (CO2) are both Greenhouse Gases, but methane holds in 25 times as much heat as carbon dioxide, so clearly we have to address methane emissions if we can hope to curb climate change!  That means dealing with food waste, cattle production, and fracking–all of which release methane.  In landfills, rotting organic materials that are buried with no exposure to air are producing methane too.  In many places that methane is tapped and burned to provide energy for the needs of the landfill facility.  Of course carbon dioxide results from the burning, but that is preferable to allowing the methane to seep into the atmosphere.

Speak Easies has a hands-on Downloadable Do-It-Yourself Carbon Cycle with engaging pictures that students can assemble to understand the processes and problems involved and to consider solutions!  Available soon on this website, but it can be purchased right now at Speak Easies Active Learning Tools for Biology on TeachersPayTeachers.

Hands-on kit to help students understand the carbon cycle and climate change

Dive into the Kelp Forest–Food Web Fun!

Kelp Frond

Are you tired of lessons on food webs and energy flow that focus on generic forest systems, some desert somewhere, or a tropical rain forest? Speak Easies’ Kelp Forest Downloadable Kit is a great way for your students to simulate a dive off of California’s coast and become familiar with some fun facts about the fascinating creatures that live in the kelp!

Did you know the California sheephead fish  changes from female to male at about age seven?  Are you aware that the purple-ringed topshell, a tiny snail 1 1/2 inches tall, is a fierce predator that rears up and lunges at its prey?

Purple-ringed Topshell

Your students will discover these facts and more as they assemble a food web from the kit’s hands-on pieces.  They’ll also learn about the upwelling that supports such rich diversity and the conditions that make a dive challenging in this area.  And using the language of uncertainty, they’ll speculate about the functions of the different parts of the kelp frond.

This is a great lesson for a sub day or when you need a break while your students are engaged.   Available here on our website very soon and on our store, Speak Easies Active Learning Tools for Biology, on TeachersPayTeachers right now!

California Sheephead