Having watched a video about biomolecules and read about biomolecules, it is time to build biomolecules! Thanks to a DonorsChoose grant last school year, we have a class set of molecular modeling kits and students used those to work through the first half of the What is the Chemical Nature of Biomolecules packet. Students learned how to use the molecular modeling kits and then used the components to model molecular oxygen, carbon dioxide, water, and ultimately glucose. We will complete the packet tomorrow, with students modeling how two glucose molecules combine to form a disaccharide, and then they will extend their learning about fatty acids and amino acids.
We worked through student questions about Lesson 20 for the first part of class, with several of the questions guiding students through the learning the textbook intended to introduce through the Salty Eights game in Lesson 21. Rather than play the game, students instead used the last part of class to begin working with molecular modeling kits (something they will be introduced to later in the textbook). Although we did not use it today, the Lesson 21 PowerPoint is available for download. We will work through portions of the Lesson 21 worksheet tomorrow, playing the game at the beginning of class.
After spending the first half of class reviewing the DNA base pairing worksheet from Tuesday, we moved ahead with a survey of molecular bonds. We focused on covalent and hydrogen bonds, with water molecules as our model molecules. Students used the molecular modeling kits to model the interactions of water molecules at different temperatures before moving on to modeling the interactions of DNA nucleotides. The lesson can be downloaded here.
As we continue through our unit on energy, matter, and organization, we will deploy our new molecular modeling kits. The kits, provided courtesy of our Donors Choose grant, will enable students to gain experience modeling molecules in three dimensions. In a previous lesson, students modeled cellular respiration using two-dimensional paper molecules of glucose and oxygen (which they converted to carbon dioxide and water using scissors and tape). We will be using our molecular modeling kits to model the process of photosynthesis, with various learning opportunities available to help explain the baggie garden results. Time permitting, we will also use the kits to model how glucose models can link together to form more complicated molecules like starch and cellulose. Students will have opportunities to model amino acids and nucleic acids as in future units.
Want to learn more about the exciting field of chemistry? Visit Theodore Gray’s Periodic Table website (look familiar?) to learn about all of the known elements. Then check out “Hunting the Elements” and skip ahead to 31:58 where the host introduces the concept of proton number as the definition of what makes elements unique. For the next 15 minutes or so, the host meets up with Theodore Gray – for extra credit, write up a summary of what you learn from this segment!