barralopolis

Brain model: somehow seemed fitting for a biology and thinking discussion

I intended this blog posting to be more specific and researched, but life is happening at high speed around me and if I want to make it professional…well it will not get written.

Last week, on the first day of class of an anatomy and physiology course (intended for pre-nursing students), we dedicated some time to a biomolecules review. I use it as a group approach: divide students in groups, assign each group a type of biomolecules: lipids, proteins etc, and ask them to look up 4 pieces of information: chemical composition, simplified diagram of structure, cellular localization, and function. After 15-20 minutes they input the info to a big table on the whiteboard, and then we discuss as a class- or should I say: I go over the table expanding and clarifying issues.

This is something I have done many times and I am familiar with the types of challenges and misconceptions that come up. So I was surprised to see one I had never seen before: for cellular localization of monosaccharides (simple sugars), particularly glucose, the group wrote mitochondria. I blinked.

In case you are not a biologist: this is a connection that at the same time makes and does not make sense. I asked the student how did they get the idea, and he said they figured out that simple sugars are cellular fuels, and that in another section of the book it said that the energy collected from glucose is harvested in the mitochondria. Ergo, glucose is present in mitochondria.

Indeed, those two pieces of information are correct separately. However, glucose does not really make it to the mitochondria (not as part of that particular process, at least): it is degraded outside the mitochondria in another process, and one of the intermediate products is the one that enters the mitochondria. Moreover, simple sugars do not tend to be associated to a specific place in the cell- as fuel molecules, they are usually taken up or released and used quickly. There is a dynamic nature to where simple sugars are present (usually briefly), and this is part of the whole idea of localization. Some cellular components have set places, others move around. A seemingly simple question suddenly acquired multiple layers of complexity that are not easy to convey in a short time frame.

On a side note: I was observing what students were doing to find the information. A few of them were thumbing through the paper textbook. Many had the book as an ebook on their laptops or tablets, and were doing word search. A large proportion of the students were doing google searches on their smartphones.

I see this a lot- students put together pieces of isolated information to arrive to a conclusion. The pieces sometimes sound similarly or seem to be related, and often students jump to the conclusion that they are related, or one derives from the other. And that scares and frustrates me.

I think that as a science educator, I am not alone feeling often helpless when faced by the lack of critical thinking skills in student populations. Honestly, I do not know or remember how I acquired my critical thinking skills. I know I have them, but I do not recall anybody explaining them to me. And very often, when foraying into educational sites I find myself confused by the ed lingo.

After that class, I had a long chat with an instructional technology and education expert, and we talked about critical thinking and the Socratic method. I will write more about some specific ideas she gave me about how to make memorization more engaging, or how to prod students through questions to arrive to conclusions.

Still thinking about this, suddenly an image came back to me from a distant past. I am in third year of college: it is our Biochemistry I class at the Faculty of Biology of the University of Havana. We are a relatively small group now: maybe 50 students. Two years of relentless Calculus, Physics, and Chemistry have withered (weeded out, as some professors bluntly say) our group from their original 150.

Faculty of Biology, University of Havana, Cuba

Professor Joaquin Diaz Brito is walking us through gkycolysis and Krebs cycle. This is pre-Powerpoint time, and this is Biochemistry, so he is writing each step with the corresponding structures on the blackboard, and we are taking notes. Hours pass as we grind through each and every reaction, enzyme, inhibitors, activators. We get to the end of it and we see the circle on the board, and the reactions starting from glucose, winding down all the way to carbon dioxide and water. We sit back with a sigh of relief. It makes sense. We get it.

Joaquin turns around, his eyes twinkling.

“Now think about this- what happens if the reactions go backward?”

We look. The static drawing on the board starts spinning, as suddenly we see the arrows going on reverse. It is a magical moment that I clearly remember after decades, when metabolism became alive in front of my eyes.

We groan. And we love it. We love Joaquin for the magic of the cell, suddenly revealed.

I need to know how to do this for my students.

Gracias, profe. You just gave me some ideas.

(while writing this, I turned to the internet. I unearthed some article references and links, but the one that warmed my heart was this one, reporting on Prof. Joaquin Diaz Brito’s teaching achievements. )