This lesson introduces beginning biochemistry students to the concept of a biomolecule binding site, such as a neurotransmitter receptor site or an enzyme active site. A simple organic molecule, the neurotransmitter serotonin, is the focus of the lesson. A pre-activity guides students in their review of non-covalent interactions prior to engaging in the lesson. During the lesson, students are asked to consider three different points on the serotonin molecule where non-covalent intermolecular for…