Post AP Bio Exam: Epidemiology Unit

This year, we actually finished the AP Bio content by the time of the exam. This left us 3 weeks of school after the exam, and time to put together a unit on Epidemiology. Way back when I taught AP Bio before I had children, I would read the class the book, Ebola, and then we'd watch some documentaries.  This time, I decided to alternate activities with documentaries and a movie.  Our schedule looked like this:

Day 1: Watch the TED-Ed Video What we know (and don't know) about Ebola and then the PBS documentary, Spillover-Zika, Ebola, & Beyond.

Day 2: Complete Virus Explorer from HHMI BioInteractive. Students could also get to it through the PBS website.

Day 3: Watch the Nova Documentary, Plague Fighters. I didn't see this available on PBS's site anymore, but got the DVD from my local library.  A quick Google search brought up this movie guide that I had students work on as we watched the documentary.

Day 4: Complete Ebola Disease Detectives from HHMI BioInteractive. First we watched the introductory video, Think Like a Scientist-Natural Selection in an Outbreak. I must confess that I'm tempted to do this activity during our Evolution unit next year.  Having to organize the different DNA segments by how many changes have happened led to some good discussions, since the changes didn't fall into neat little groups. Also, the video includes clips from the other documentaries we watched, so separating it from the time we watch the other videos might be helpful.  By the way, I laminated the DNA sequence sheet and cut the sequences into individual strips to make it easier for the students to group them (and to help them last for another year).

Day 5: Watch Surviving Ebola from Nova.  I also got this DVD out from my public library.

Day 6: Complete Disease Detectives. This came from the Life Sciences Learning Center by University of Rochester. (I just had to request membership and a link to all of the activities was sent to me.) This activity involved some reading and answering questions, but also included some hand-on components. We did find that it was easier to see the antibody-coated bead test when we dropped the samples directly onto our black lab tables.  It was too hard to see if the solution became cloudy on the white paper.  I should have printed the test circles on colored paper. (The instructions did warn about using white paper for this test.)

Day 7: Watch the movie, Contagion. I found a movie guide for Contagion at moviesheets.com. I made a couple of changes and put it into this google doc. The class loved the movie, although they balked at how it ended.

Day 8: Watch a movie (that was not Ebola or outbreak related).  I gave the students the choice of The Martian, Jurassic Park, or Jurassic World. Jurassic World won, but we didn't see much of it, because we spent extra time talking about key concepts to review for the final exam.

We only meet 3 times a week in blocks and some of these days spilled over into the next day. This happened especially since on each day we also did a review Kahoot of a different unit and practice essays to prepare for our final exam at the end of the year.

My Favorite Fish Lab

Two years ago, I was planning to do a lab with the heart rate of Daphnia. I had the lab form all prepped for my students, but then realized that I didn't have enough time to order the Daphnia. I went to Google for some ideas and found some great experiments with goldfish (AKA feeder fish). Those I could go to Petsmart for and they only cost $0.14-$0.29. One of the labs I found was the Fish Temperature Lab from Biology Corner, and others from Laying the Foundation, Inc., and a lab by David L. Umbarger in Montezuma-Cortez High School, Cortez, CO, So, for the last two years, we've been doing a lab with goldfish (feeder fish) in both regular Biology and AP Biology that is a combination of these labs.  We only have a few modifications in the lab between the two levels of classes. In this one lab, we tie in the concept of endo/exothermy, the respiratory system, and the circulatory system.  Last year, we also tried a tie in with the endocrine system, although it was difficult to notice results.

We start the lab by putting a fish in a beaker and then putting the beaker in a water bath. We measure the respiration rate either by counting the opening of the fishes' mouth or the movement of the operculum. Students add warmer water to the bath and continue to measure respiration rate. After we finish with the slightly warmer temperatures, we add ice cubes to the water bath and continue to measure "breaths" as the temperature decreases.

For my regular Biology class, this provides great graphing practice as they gather and find the class average and graph the results.  In AP Bio we use this as an opportunity to talk about determining Q10 for fish respirations and talking about what that means.

After giving the fish some time to reaclimate to aquarium temperature, we move onto the next part of the lab. Actually, we usually set those fish aside to allow them to reaclimate and use the fish we didn't use in part one. Each year I've done this lab, I've had to convince students that we won't kill the fish we use in part 2. For part two, we wrap the fish in aquarium water soaked cotton and look at their tails under the microscope. Students are amazed once they see the blood vessels in the fish tails with blood cells actually moving through them.

Last year, in part 2 we then added dilute adrenaline to the fishes' tails to observe the affect, but we had a hard time noticing a difference. We talked about the expected results (faster blood flow) and what the actual results should have been (slower blood flow since the tail is an extremity).

I am happy to report that both years we've done this, all of the fish have survived.

Here's the lab form that I give my AP Biology class. Here's the form I give to regular Biology. I also give them directions separately to save me some photocopies.

The Immunology Card Game for AP Biology

We do human body systems at the end of AP Biology.  I like to save my favorite for last.  The only drawback is that by this time of year we are starting to lose some steam.  I try to teach this unit almost entirely by activity.  I started searching in early Spring for ideas of what to do with immunology.  I found an article in the American Biology Teacher, "The Immune System Game" from the May 2015 issue. I decided to make my own "characters" for the game just to make copies a little easier.  After a test run playing the game with my husband, I decided that I also needed to rewrite the directions in an easier to follow way. There are so many steps in the process and what you do changes depending on what cell from the body you are looking at. I opened a google drawing and made a flow chart of the directions. It seemed to work well with the class.

The "bad" guys...

We did run out of time before we got to simulate a viral infection. Next year, I'll have half of my groups "play" the bacterial infection and the other half "play" the viral infection. Then we'll have a group discussion about the differences.

The "good" guys...

I also found in the trials that even for the primary infection, the body ended up with a lot of immune cells--so it didn't demonstrate the advantage the pathogens have the first time around (in the primary immune response). We didn't have any trials where the pathogens won over the immune system. I've changed the flow chart to reflect an increased reproductive rate for pathogens and a decrease in the reproductive rate of the macrophages.

Here are the files I made for the game:

• Key to Immune Characters
• Antibodies
• B-cells and Helper T cells
• Cytotoxic T cells
• Phagocytes
• Bacterial Pathogens
• Virus Infected Cells
• Plasma Cells and Cytokines
• Immune Game Flowchart (Bacterial)
• Immune Game Flowchart (Viral)

After the simulation, students diagram the immune response on a white board using the cards from the immune system game. They certainly understood the time difference between the primary and secondary immune responses after this game. Next year, I also want to emphasize humoral vs. cell mediated responses in their diagrams.

Update: I've worked on making this virtual and you can read about it here.

Nervous system

When it came time to tackle the nervous system, I decided we needed to be as hands-on as possible, working with models to help students understand what was going on in this complex system.  I chose three activities for us to do.  We did Pom-Pom Potential from http://teach.genetics.utah.edu/, then we did the Nerve Cell Communication activity from the Life Science Learning Center of the University of Rochester. (It's easy to request the link to be able to access their library of activities.) We finished up with a fun reflexes and reactions lab.

Doing the activities in this order brought us from micro to macro, but I think next year I'll reverse it and go macro to micro so students can go from what they can identify with (reflexes and nerve cell endings) to the more abstract of action potentials.

We had some good discussions about the membrane potential graph of a nerve impulse that was in the question sheet I made to go with Pom-Pom Potential. I would have liked to spend more time talking about the "macro" part of the nervous system of the nerve impulses traveling through the body and the benefits of reflex arcs. Hopefully each year I will tweak this to be better than the year before.

PS-One of my students was "babysitting" for a Junior health student during this activity--thus the doll in the corner of the pom-pom picture.

Combining Constructions and Radians

We ran out of time in our last topic of circles to go over circle constructions and radians. I felt it was best use of time to give a test on a day I had to be out, so I cut those two topics from the test. I have some more freedom with our next unit, so I had put together student notes for each of those cut concepts, treating them as separate ideas with radians coming first and then constructions. A couple of days before the lesson, I was struck with an idea. Part of the constructions that students were doing was to find the center of a circle. Then for two of the constructions they also had to work with the radius. Why not combine practice finding the center of a circle and the radius with explaining the concept of radians?

I ripped apart their notes and just gave them the construction instructions first. Several students asked why there were staple holes in the one sheet of paper I gave them. I explained that I had changed my mind about how we were learning our last two topics. Once we had gone over how to find the center of a circle, and constructing inscribed squares, equilateral triangles, and regular hexagons, I gave them a cardboard circle from the top of a pie tin. I asked them to use constructions to find the center of this circle. Then I explained that a radian is another way to measure an angle and that one radian is the size a central angle has to open to intercept an arc the length of the radius.

I had them use a measuring tape to measure the length of the radius and then curve the measuring tape around the outside of their circle, repeatedly marking the length of the radius around circle until they ran out of room. I asked each group how many radii they could fit around the circle. Fortunately, they all said 6 with a little bit of room left over.

We talked about the circumference of a unit circle and that it would be 2𝜋. Then we estimated what 2𝜋 was--about 6.28.  Light bulbs started for some, that the little bit of left over on their circle represented the .28 of 6.28.  Then I handed out their radian notes and we talked about how this idea related to the formula for arc length with radians.

I threw a lot at them today, but I am hoping that it was the start of a solid understanding of radians as they prepare to go into Algebra 2 next year.

Here are the notes that I gave them to go along with this lesson.  I gave them the constructions page first though, and then the radians and arc length pages.  The questions included are from old Geometry Regents exams.

And Then There Were Circles

A few weeks ago I shared with a couple of my colleagues my excitement over finishing putting together the details for the rest of our year in AP Biology. Within that week, administration came to me to ask if I would be willing to take on a math class for the last 6 weeks (+ Regents exams) of school since one of our math teachers was leaving after Spring Break. His Geometry class met for 3 periods that I was already at school for (and was not actually teaching), and only one other day for a double period.  I agreed to take it on. Fortunately, the class only has two more topics to learn before we start studying for the Common Core Regents Exam in June, and they are both fun, hands-on topics.

I met with this class for the first time this week and we jumped into circles and circle theorems. I had read a couple of math blogs about circle theorems from Mathsville and Mr Reddy Maths Blog. I also had about 15 hula hoops from when I had taught a Sunday School class and we did a weaving project. I pulled out the twine and yarn and we got to work demonstrating several of the circle theorems. Can you guess what theorem each hula hoop represents? There are several other hula hoops of theorems, but it's very hard to see the yarn in the pictures with students holding them.

I also put together some graphic organizers for my students to keep track of it all. We started with definitions and then moved onto theorems.  For theorems, they worked on adding the diagrams, I gave them the words. This made for a fun first class with this group.

Egg-less Chicken Embryos and Real Science

Trying a lab for the first time is a great learning experience.  Sometimes we use labs that "work", but it doesn't give us the chance to think through how we could improve an experiment or procedure we've tried to figure out. The students hear from me that real science is trying experiments over and over, making tweaks, and sometimes going back to the drawing board altogether. Trying to hatch egg-less chicks has been a great experience in working on procedure.

Students had a chance to try again when the yolk broke, or the egg was rotten, and because of it, they became more confident in what they were doing. Finally having some success was very exciting. And to see the embryo development that happened in just one day was amazing. I am regretting not going into school on Saturday since when I checked Sunday our best embryo had made so much progress.  I don't know that it will progress much further though, since it looks like the yolk has broken.  I'm still impressed with the development that we were able to see, and now we have more ideas of what to try to make it better.

One of the problems we encountered was too many cups in the oven--next time, no more than 7 since cramming 8 in lifted some of the petri dishes. The embryos with the lifted petri dishes dried out and died. Also, we should only use the eggs with embryos that have made it to the stage of seeing the heart beating.  The younger embryos did not progress well for us. I'm also hypothesizing that it would be better to err on the side of the oven temperature being on the low side instead of on the high side. One last change was to not push down the plastic wrap as low, so the egg is closer to the top of the cup. The theory is that it will leave less air for the moisture of the egg to evaporate into. We're trying to stop dry-out.