Modeling Checkpoints in the Cell Cycle

I am always trying to find ways to make the concepts we talk about in AP Bio come to life (no pun intended), especially during the first 6 units which deal primarily with molecular biology. In class, we were working on the cell cycle, focusing on the three checkpoints and the cell regulating itself so the process of making more cells doesn't go awry. Late one night an idea popped into my head, so as my husband was trying to go to sleep, I was busy scribbling notes for a new activity on a post-it note (as seen in the picture below).

 I was thinking about all the cyclin production for the checkpoints and it reminded me of the competitions I've seen in some reality TV shows. On several occasions, a team has to fill some container with water/oil/sand before they can move onto the next part of the competition. It made me think of cyclin reaching a critical level before the cell moves onto the next part of the cell cycle. 

I had had enough of water messes with the labs I've done with my physical science class this year, so I couldn't bring myself to do a race that included sloshing water. Then I remembered that my classroom has inherited an unusually large number of cotton balls, so many that I'm fairly certain we can do the respirometer lab for another 100 years without needing any more cotton balls. As a result, cotton balls represented cyclin. I put together cards for each job in our cell cycle model. It begins with organelle drawing to represent the G1 phase of Interphase as the cell is growing/maturing. At the same time the first cyclin producer is adding "cyclin" cotton balls to a bucket to represent the buildup of cyclin in the cell. Once enough organelles were present and the cyclin had reached a critical level (up to a piece of tape on a bucket), the cell could move onto the next part of the cell cycle. Here the DNA was synthesized. We just had two pop-bead chromosomes that had to be replicated exactly. While the DNA was copied, a second cyclin producer was working on filling the bucket to the critical level. 

If both the DNA replication completed correctly and the 2nd cyclin reached the critical level, the cell would move onto M phase through anaphase. Again, once the critical cyclin level was reached, the cell moved on, completing M phase and going though cytokinesis. And the process could continue. Also during this process, there was a cell cycle checker to make sure the cell was going through the cycle correctly and would halt cyclin production and therefore the cell cycle if anything went wrong. They could then send the cell into G0, its non-dividing state.

The link to the job cards is here.

Cellular Respiration Digital Diagram

Last year I blogged about the cellular respiration diagram that I had saved from college and use in class with my students here. After a Google training last year, I decided that I would attempt to use Google Drawings to make the respiration diagram. I spent more time than I care to admit, but got the diagram put together here and out to my students.

We worked it the same as last year. They worked on labeling the diagram first and we talked through it and even acted out oxidative phosphorylation. Then they completed their guided reading questions. Students comment each time we do it that way, how much more they understand the reading questions for this chapter.

Although it may look like there are lots of details for glycolysis and the Kreb’s cycle—for those we focus on what goes in and what comes out. We spend plenty of time discussing the significance of NAD and FAD “boats”. This year they coined NADH and FADH2 the party boats since they are full of high energy electrons.

We wrapped up our discussions today with the Mystery of 7 Deaths case study that you can find here. I loved the reasoning I was hearing!

Penny Density in Physical Science

One of the labs we did this year in Physical Science when we were studying density was one called "Coin Operated" from our textbook, Holt Science & Technology: Physical Science. Lab groups are given a set of 10 carefully chosen pennies that they mass individually and are asked to divide into two groups. (Their masses give a big hint about how to divide them.) They also use the water displacement method to determine the volume of the pennies. Students find the density for each set of 5 pennies and then are asked to determine what element they are likely to be made of. In an ideal world, one set will be close to the density of copper and the other close to zinc. Then students are tasked with figuring out how they could divide the pennies without an electronic scale. Eventually, students realize that older pennies (pre-1982) are made of copper and new pennies (post-1982) are made of zinc.

Our first test included a lab practical section and I wanted students to find the density of a penny and use that information to determine if the penny was from before 1982 or after 1982.  Of course, how do you hide the date from the students?  Fortunately, one of the few souvenir items my husband and I  let our kids get when we go somewhere special are those squished pennies with the logo of whatever place we are at. One of my daughters helped me round up four of these squished pennies so I could have four test lab stations going at once. Believe it our not, it turned out that two of them are pre-1982 and two are post-1982. Since the test, I've found two more, both post-1982.

Mini-Poster Presentations

When I look back at each year I've taught AP Biology since I returned to the classroom, I can give each year a theme.  Year one: survival (myself brushing up on all the content and the new AP exam), then year two: tweaking the alignment of the class with the Essential Knowledge statements and Learning Objectives for AP Biology from the College Board, and now year three: reflection and revision. I've changed how I grade formal lab reports (a blog on that will have to come later) and we've added a different type of lab report.

So, we're trying something new in AP Biology this year--the mini-poster presentation for a lab report. The formal lab report still has its place and we'll do 4 or 5 of them this year, but I felt like we needed something else to help expand the student's repertoire of presenting and defending their findings. I read the blog post on Authentic Peer Review by Brad Williamson in the KABT Bio Blog, looked at his linked resources and decided to run with it.

This week students picked their item to core and determine the molar concentration and water potential of. This is part of the standard AP Biology lab on diffusion and osmosis. Before the lab I had prepped the 0.2M, 0.4M, 0.6M, 0.8M, and 1M concentration of sucrose, colored each a different color, but didn't label them. That just gave an extra "mystery" for them to solve. Each set of lab partners also had a labeled and laminated tri-fold folder made from two Manila folders glued together and a huge supply of various post-it notes (even graph paper ones!).

They wrote their methodology as they went through the lab. Their presentations came together as they collected data and began their analysis.

Once the reports were finished, I gave each lab group a printed copy of the rubric I'll use to grade their presentations. Then all students had to go around to each report and make a suggestion for the authors of that report that they believed would help improve that report according to the rubric.  I give each group an opportunity to revise their presentation before their final submission to me. This process gives the students both experience with peer review and the ability to do revisions. Then I'll grade the reports using the same rubric.

After the reports are graded, we'll be able to peel off all of the post-it notes and start our next presentation.

The class enjoyed the process of putting the lab together. One lesson I've learned though as I've been buying specialty post-it notes is to encourage the students to write out their first draft on scratch paper and then transfer to the post-it notes when they think they're ready.

Cell Membranes and Bubbles

I was happily reading through the Facebook feed of the AP Biology teacher group and saw a post from a teacher who had just done a bubble lab to teach properties of cell membranes. It looked like fun and I was about to embark on cell membranes. The lab is from Jeremy Conn of Clear Biology.  You can download the lab from his site here. I just used his resource without any editing--which is handy since I'm having a hard time keeping up with everything to do. I made some bubble solution on a Thursday, and we did the lab this past Monday.

I think sometimes I forget that even though I teach Seniors, they are still kids.  (Actually, we should all be kids at heart.) The students loved this lab and had so much fun playing with bubbles.  And in the end I felt like they significantly improved their understanding of cell membranes and the fluid mosaic model.

As they progressed through the activities, they got more excited. My favorite was the loop of thread that opened to a circle and then could move around the bubble frame like a transmembrane protein.

As they were cleaning up, I heard conversations about how they should do this bubble lab with their fourth grade buddies. (One advantage of being in a K-12 school.) Love it!

Monomer to Polymer Game

About midway through the year last year, I stumbled across the National AP Biology teacher Facebook group. I must confess that now most of my time on Facebook is reading discussions in the group and not as much time keeping up with what my friends have had for dinner. =) One of the benefits to starting the school year so late in New York (after Labor Day), is that I actually have time to put together ideas I find by people who have already started their school year. A post from late in the summer this year was by Mary Neimeyer who made up a polymer building game to help drive home the understanding of dehydration synthesis and hydrolysis. Then another teacher in the group, Kelly Riedell added some more details and cards. I pieced them together and decided to make my own cards and modify the rules a little. We finally got to playing the game today and it was a huge hit.  From the group that got cut-throat competitive I heard, "I can't believe we're yelling about monomers and dehydration synthesis!" The other group asked me if they could have the game pieces to play it in study hall.

I put together the directions that Kelly Riedell made with Mary's description with some modifications and made playing cards for the game.  The directions can be found here. And the game cards can be found here.

Modeling Enzyme Activity with Pool Noodles

Enzymes and how they function is such vital concept to understand for AP Biology, but it can be challenging to understand something that you can't actually see.  Last year was the first time we worked with pool noodles trying to demonstrate how enzymes work. Here's the blog post about it. I thought it went well and decided to do it again this year. Since last year, I have discovered Expo neon window markers.  This year, instead of labeling our pool noodle enzymes on white boards, students just wrote right on their lab tables. It looked fabulous!

First Day of Physical Science (Part 2)

Today was actually the first day of Physical Science.  I teach this class at a homeschool consortium that started today, so it is certainly falls into the category of a non-traditional classroom.  I only see this class for one 90 minute period a week, and I design the class with all hands-on labs to complement whatever chapter/topic they are reading and studying at home.

After we finished with our team building activity with Legos and clue cards that I blogged about earlier here, we moved onto the Mini Metric Olympics. I used the direction cards from this post on Math = Love. The only thing that I had to do besides gathering materials was create an answer sheet that would fit into their notebooks.  I also wanted them just to find their percent error, so I only included a column for that, not error.

The kids loved the activity and I actually overheard one of the students say, "This class is fun," as her group was moving from one station to another. That's a win in my book!

Lots of measuring going on...

...and estimating too.

First Day Plans for AP Bio

Although for the last two years I had been starting AP Bio with a lemonade lab (after brief introductions), I decided we needed a change this year. I loved the practice with experimental design students got, but the lab itself didn’t add anything to the content of the class. Through the AP Biology Facebook community, I saw a water lab that helped introduce statistics. They'll perform several trials to determine the number of drops of water, water with soap, or rubbing alcohol that will stay on a penny without spilling over.  Not only does this lab give statistics practice, but also fits with the current content--biochemistry. Over the summer, students read the water chapter and this lab allows some review of this material.

I won't include the lab document since it isn’t mine to share, but I did make a google sheet to accompany it. This is the link to the google sheet I made for students to put their data. I put all of the formulas in for them this time, since I wanted to focus on the stats themselves. I also combined their data to get sample sizes large enough for +/- 2SEM to work for the 95% confidence interval. We’ll do one more lab activity where I give the formulas before I task them with an inquiry lab and they have to do the stats on their own.

I do start the class with quick introductions to me and to the class itself. This year the introduction will come through a Kahoot! I also have students fill out a google form to help me get to know them better. Then we jump into our lab. I'm also using a new way to split kids into lab partners. In the past I have let them choose partners, but it doesn't always work well. This time they'll pick a card and figure out their lab group and lab table. The colored cards will each be on a different table. It'll also be a quick check of how their summer learning went.

Prepping the Classroom

We’ve been allowed back in the building, so I’ve been working on prepping the classroom for students. One of the first items I had to work on was putting together the computer. Fortunately, last year I put numbers on all of the wires and took pictures before unplugging all of the connections and storing it away. It made putting it all back together so much easier. Last year was a guessing game (and it took a few guesses to get it right).

Last year I had made the classroom bulletin board the AP Biology FRQ word wall,  but decided that this year, the word wall would create a boarder above the windows.  I needed to add a few more words, and fortunately Cheryl Ann Hollinger had posted FRQ key words with definitions for the AP Biology community. I chose several words that we didn’t already have, put them into the same format as the existing words, printed and laminated them. I put them up with sticky stuff--and so far all the words have stayed up. I realized today that it’s hard to take a picture of a wall with windows on a sunny day!

Another of my projects was curtains for the door windows. During lock-down drills we have to cover those long, skinny windows. What we had been using was a line of construction paper tapped together. This summer one of my colleagues pinned a cute classroom door window curtain idea. That was the inspiration. I bought a pack of fabric strips at Walmart and started sewing. In the pinned blog, the person had used a dowel and drawer pulls for the curtain rod. Since we use this room for science and math I decided it would be easier and more subject specific to use a ruler for the curtain rod and binder clips to hold it in place. I’d like to be able to pull the curtains further away from the window, so I’m planning to buy command hooks with metal hooks as tie-backs.

The last thing I tried wasn’t actually a room prep, but experimenting with pens that will write on our lab tables. When we work on review games and other modeling activities, I want students to be able to use their tables as their canvas. I’ve seen pictures of classrooms where teachers were using them and thought it would be a fun addition to the classroom. I ordered Expo neon window dry erase markers as well as Versachalk chalk markers. Both types worked well. In the picture at the top of this post, “Welcome to” was written with the expo marker and the rest was made with the chalk markers. I decided to leave the writing on the desk for a couple of days to see how difficult it would be to get the writing off of the table. I had to resort to a magic eraser for the chalk, but when I only left it on for two hours, it washed right off. We’ll just be sure to wipe the desks down by the end of class. I love the vibrancy of both and can't wait to use these markers in class.