Why Does Mitosis Matter?

This year’s Mitosis unit is running in this way:

I started the concept of Mitosis by talking about Henrietta Lacks and her mysterious cancer cells, which of course divide through Mitosis. This is such a great way to introduce a seemingly dry molecular topic because it gives the students a reason to care. In 10 minutes, you can pull in ethics, medicine, history and civil rights all surrounding this topic and get your kids fired up about the injustice of it all. The Power Point that I created for this lecture is here: Mitosis

planaria planarian2

 

 

 

 

 

 

After discussing the big picture about Mitosis, what it is, why it happens, how cells know to do it, I then introduced my students to our next organisms of study, the Planaria. Planaria are fascinating and tangible and the kids really do feel that they are doing science when they are “creating” new worms. Howard Hughes Medical Institute has a GREAT lesson that revolves about Planaria regeneration and you can access that information here. I love this lab for so many reasons. You can take it as far as you would like. The lab sheet explains exactly where and how to cut the worms so that they will regenerate in a predictable manner if you are working with younger students, or, you can let your students run with it and explore this idea on their own. I let my kids have as many worms as they wanted and to cut them however they wanted to see what the results would be. Also, if like me, time is not an issue for you, you can let your students explore the regeneration rates of these worms in different environmental contexts. My students this year were interested in the affect water temperature would have on the worm fragments and the affect light has on the worm fragment regeneration. Planaria generally repel light so my students wanted to see if this would have an affect on their regeneration rates…we will have to wait a few more days to see on this one.

For outside work following this lab, I have asked the students to research various labs around the globe that are extensively researching Planaria and why they are doing so. This is to tie in a real life application of what is happening in our lab to what is happening out there in the world.

As a final wrap up to the Mitosis topic (before diving into DNA and then Meiosis), I addressed the specifics of the DNA function and location during duplication. I modified an existing activity this year to use cooked spaghetti noodles to represent Chromatin and am having the students create a Snap Chat story involving the manipulation of their noodles through the different stages of Mitotic division. I wrote another post about that and you can find that here, Mitosis With A Side Of Sauce.

As always, if you use or adapt any of these ideas, please come back and share with me. Let me know how it’s going and what worked or didn’t work for you. And, if you plan to publish these activities anywhere, please refer to this Blog as the source and me as the author.

Thanks so much! Happy dividing 🙂

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Mitosis, With A Side of Sauce

Mitosis, With A Side Of Sauce   I have found that Mitosis and Meiosis can be complicated to teach because like much of molecular biology, my students can’t get their hands on the process to fully understand it. I have done lots of activities in the past using candy or pipe cleaners but this year I am doing something a little differently, I have decided to use cooked spaghetti noodles to simulate the chromatin. I am including the lesson plan below. As with other lessons and projects, if you use or publish this material, please cite this webpage as your source and me as the author…thanks so much!!

Lesson Plan: Mitosis, With A Side of Sauce

Goals and Objectives:

The goal of this lesson is to give the students some tangible ownership over the process of mitosis without getting caught up in the details of terminology. This lesson can be used as an introductory activity to the process of Mitosis or it can be used as a follow up to a discussion/lecture on the process.

Rationale:

I have found that students have a hard time conceptualizing what is actually happening with the chromatin/chromosomes during the process of mitosis. The diagrams in the books and on the web are too abstract, in my opinion, for them to achieve any kind of real life connection with. This activity gives them 30 minutes to take the process step by step and really show whether or not they get the big picture and understand the details. This is a good alternative to the pipe cleaner activity and is a bit better, in my opinion, because they are using the same noodles throughout the entire process instead of getting new pipe cleaners along the way.

Procedure:

Materials Needed:

1. Give each student the following:
~ 10 cooked spaghetti noodles
~ a paper plate
~they will need their smartphones or cameras

2. In respect of time, I think it would be best to cook your spaghetti noodles at home before the activity. You could also have the students cook them for homework and bring them in. You may want to break the noodles in ½ before cooking so they are easier to work with.

3. Have students partner up with their lab partners

4. Have each student show their knowledge of mitosis through the manipulation of their spaghetti noodles. Have them start with their noodles spread out on their paper plate (as chromatin) and tell them that your whistle is the Progression factor hormone, Epidermal Growth Factor (EGF) that instructs the cell to enter Mitosis. At this point, turn your students loose and let them express the steps of Mitosis using their spaghetti noodles. They need to document each step by taking photos and turning these photos into a brief movie. This can easily be done using Snap Chat movies or Instagram movies. If you have an Instagram page for your science class they can post it there or, you can create a snap chat account for your science class. The only problem is that the snap chat movies only last for 24 hours once they are shared so you can’t keep them indefinitely.

  1. When completed, have each group share their movie with the class to look for inconsistencies or to identify common themes.

Assessment of Student Learning:

Every lesson does not need a written test or quiz, but each lesson should check for student understanding. You can do the traditional assessment and ask the students to answer questions on the process of mitosis or you can also transfer the learning to the lab setting and set up a number of microscopes around the lab with pre-determined (by you) slides of onion root mitotic division and have the students identify the stages based off of their observations.

Activity Extension

You can modify this lesson to teach the process of Meiosis as well. You can do the activity as described above but this time make 2 pots of spaghetti noodles, one regular and one in colored water (with food coloring, green or blue works best for me). Give each student 10 noodles, 5 regular and 5 colored, and have them show the process of meiosis (including crossing over) with the noodles. It will be easy for them to see the specific steps of the process because of the different colored noodles.

An Unexpected Reflection

I am having my 10th grade Honors Biology students keep a portfolio of their Project Based Learning activities this year. The portfolio is organized with a title page, an index of projects, an abstract page which provides the reader with a short paragraph explanatory excerpt of each project and, of course, the actual projects themselves.

One of my students, a particularly shy and quiet child, started his abstract page with a paragraph reflection of what he believed the purpose of our PBL activities are. I swear that his reflection nearly brought me to tears because he nailed it exactly. He fully gets the purpose of these activities and he is getting out of them exactly what I am hoping for.

Project Based Learning is what happens at the end of most chapters in our Biology class. We are assigned a goal to accomplish with a partner, and can go about that goal however we like. These projects are like real world problems based on our learning in the classroom. They are preparations for the real world, where creativity is rewarded and recognized over only pure intellect. They allow us to explore subjects with our own free will and experience another side of science, the real side.”

I could never ask for more than this. My heart is smiling today 🙂

Photosynthesis PBL – Part II

About 4 weeks ago, I introduced my Photosynthesis PBL problem to my students. The description of the project that I gave them is as follows:

Photosynthesis PBL – Alternative Energy Resource For Residential Establishments

There are many people in this country who live “off the grid”. “Off the grid” living is becoming a popular choice for people looking to reduce their carbon footprint, assert their independence, and avoid reliance on and abuse of fossil fuel usage. “The Grid” refers to the power grid, which is a system that delivers electricity directly to your house from the source. Power is supplied to homes in the form of electricity, natural gas, water, and telephone lines.

One-way to off-set power needs is to use solar power and convert that into energy. Solar panels are becoming a popular means to capture light and turning it into usable energy through photovoltaics. The problem with photovoltaics is that you cannot store the energy for long periods of time and the batteries used to temporarily store the excess energy are expensive and inefficient. Not to mention that if there are long periods of time without exposure to sunlight, your energy stores will become depleted.

Your company has come up with a solution to Photovoltaics. You are tasked with designing a structure that will recycle the excess CO2 in homes and turn that CO2 usable energy for the home. This structure will function much like a chloroplast in that it will take CO2 and H20 and repurpose those materials into usable energy that can be continuously supplied to the home for power.

Your proposal (< 2 pages, including figures) must include a description of the following:

(1) The structures used and how they correlate with structures within a chloroplast

(2) Diagrams and figures that will show relationship between energy recourses used before implementation of this device and after implementation

(3) A descriptive paper explaining the process, in detail, of how the structure works

(4) A physical model of said structure

The students did a PHENOMENAL job with this project. I am including a few pictures of the physical models that they created. I also allowed them to created 3D computer models on a software like “TinkerCad” if they so chose. Again, as with every PBL I have ever assigned, the outcomes were more than I could have ever hoped for. These kids amaze me with their knowledge and creativity and I truly believe it has everything to do with the process of project based learning and the freedom to create whatever they want as a result of their research.

Extreme Green Machine
Effective system consisting of three parts: direct air capture mechanism, the panel, and the photoswitch
Photovoltaic partnership
The use of photovoltaic cells will power the combustion of methane compounds to create energy
Chlorophyll Roof
Extract excessive leaf chloroplasts and isolate the Chlorophyll a & b to create an energy capturing system on the roof of the home
"we propose a structure that will use CO2 & H20 from the atmosphere and convert the 2 compounds into hydrocarbons which will be combusted for energy. This will be accomplished using the liquid catalyst, Salt of Copper"
“we propose a structure that will use CO2 & H20 from the atmosphere and convert the 2 compounds into hydrocarbons which will be combusted for energy. This will be accomplished using the liquid catalyst, Salt of Copper”