Microscopy in Anatomy & Physiology - Central Nervous System Lesson

 Following up on my last post regarding microscopy as a teaching tool, I want to share with you some of the work my Anatomy and Physiology 2 students completed this semester with prepared slides of nervous system tissues - spinal cord and brain. Once students have successfully focused the microscope slides, I encourage them to use their cell phones to capture photographs of their views.  

Cerebellum - student cell
phone photograph 

Cerebellum - Student drawing 

    

With many years of experience, as the teacher, you are very familiar with the tissues and their appearances that your students are working with, and what to expect when you look at their drawings. I've seen several lovely drawings of water bubbles (wet mount slide preparations by students) or dust specks. A couple of years ago I would have asked the students to step aside and let me take a look through their scope to assess their focusing skills. During COVID, I did not check looking through the scopes as we were practicing distancing. (When students were done working, I had them use alcohol pads to wipe down the eyepieces and knobs) That's what makes the use of phone camera shots in the lab another good assessment tool.  In addition, you can zoom in on the photographs and see even more details. Plus the students will have a record of the slides that they can refer to and study from should you plan on a lab practical. 

For this lesson, I wanted the students to identify key features of the tissues under observation. I generated the lab sheet below with the instructions for coloring and labeling. Students had the list of vocabulary terms that needed to be labeled. 

Central Nervous System Microscopy Lab Sheet 
Student Work Sample 

Density Column Lab

Egg Drop Density Column Lab

It was midterm season once again and I was looking for a new lab for my Chemistry students to complete for their practical portion of the exam. I went hunting for a lab that would incorporate prior knowledge and showcase the student's ability to follow a lab procedure with little to no instruction from me, utilize the measuring skills that we have worked on all semester, demonstrate their understanding of laboratory safety rules, and to work independently. I found the answer in The Egg Drop Lab.

Because of time constraints (a two hour exam period that included a written portion) I set up the lab stations to include four liquid samples (I chose dark corn syrup, dishwashing liquid, vegetable oil, and rubbing alcohol into which I added blue food coloring) in graduated cylinders and indicated the empty mass of the glassware. I randomly filled the cylinders with differing volumes and the students had to calculate the density and predict what would happen if they added the four liquids to a test tube. Then they built a column to test their predictions. The lab procedure then asks them to predict where in the column water would settle and then to test that prediction. The next step was to determine the density of an egg and predict where in a column it would end up when dropped in. To minimize the amount of material used, I built the column using the student's input. The results are shown here. In addition I colored water with red food color and added it to the column before dropping in the egg.

What was really nice about this lab is the author designed this for an Earth Science course so it was an opportunity for me to have my students see the connection between what they have learned in Chemistry as it applies to the other sciences.