“Let’s go! We made glucose!”
Scientists in 9th grade Biochemistry I are modeling, building structures to match the chemical reactants, and then products of formulas they know from prior studies of photosynthesis. Their teacher directed them by saying, “start by writing down what you already know are the inputs for photosynthesis… You will need to start by building six of each of these and later you will see why you need six.”
This week, in small groups, students used atomic model sets to build six carbon dioxide and water molecules, then used the “HONC” atomic bonding rules they have learned to puzzle out a way to produce glucose. For homework, students watch videos and take notes from their teachers’ explanations. In class, they bring chemical processes to life as they work with their group to figure out how to use the bonding rules and all their starting pieces to build one glucose, knowing that six oxygen molecules will be left over.
As they work, they noticed and discussed things like, “Is that really the shape water makes? Why does it bend up like that?”
Is that really the shape water makes? Why does it bend up like that?
And, “If we put all the remaining pieces in a line, it doesn’t work. This carbon doesn’t have enough bonds… Maybe it can’t just go in a line?”
After each group successfully produced glucose, their teacher modeled how multiple of these glucose monomers react in “dehydration synthesis” to produce longer chains, like cellulose (fiber) or starch. Students connected to prior learnings about how celery has very noticeable strands of plant fiber in it, then wondered, “If making the fiber with dehydration synthesis releases water, why does the water stay in the celery?”
And, “Is that the same thing as when you feel dehydrated?”
After their modeling and discussion, students explored a dataset their class collected during the most recent regional smoky air event, which they will work together to analyze then submit for publication as possibly one of the first articles showing statistically significant local effects of air quality (measured using EPA PM 2.5 data) on temperature!