HHMI Undergraduate Program Activities
Kenyon College 1997 Annual Program Report
BIOLOGY
A major focus of our efforts has been to improve laboratory investigations in cell biology. We have purchased a CellScan (Scanalytics) digital imaging system using deconvolution software to obtain high resolution images of single focal planes of cells and tissues. Students can now investigate various aspects of cellular architecture, in ways not previously possible at Kenyon. The following courses have already begun implementation:
BIOL 9-10 Introduction to Experimental Biology
This laboratory class introduces the student to the processes of investigative biology and scientific journal writing. First-year students used the CellScan to examine the effects of increasing cell proliferation rates on the cell cycle in Drosophila tissue culture.
BIOL 67 Experimental Cell Physiology
This laboratory course trains students in modern standard techniques of cell biology, such as protein and lipid separation, cell permeability, cell motility, and mitochondrial function. The CellScan was used to identify cell types in primary cultures obtained from chick embryos and to compare their morphologies.
BIOL 95, 96 Honors Research in Biology
Honors research students used the CellScan microscope for several projects. One involves describing the subcellular localization of a protein during oogenesis in Manduca sexta. Another is the description of cytoskeletal rearrangements that occur during the gravitropic response of Phycomyces.
Future implementation ofj the CellScan will also include these courses: BIOL 64 Principles of Gene Manipulation; BIOL 22 Experimental Developmental Biology; BIOL 46 Experimental Plant Physiology.
CHEMISTRY
CHEM 17, 18 Chemical Structure and Reactivity
This year-long honors level laboratory is open only to first-year students
with strong secondary school preparations in chemistry. The course provide
students opportunities to investigate chemical systems much as practicing
chemists would do. Beginning next year, the HHMI funded instruments will
be utilized also in the "regular" level introductory laboratory
CHEM 13;14, Introduction to Experimental Chemistry, having an enrollment
of about 50 each year.
Students recorded the UV spectra of several compounds present in commercial
sunscreen preparations, investigating the relative effectiveness of these
compounds as absorbers of UVA, B and C radiation. They investigated relationships
between molecular structure and UV spectra. Future labs will develop many
advanced molecular investigations.
Students were introduced to synthetic chemistry by synthesizing methyl
salicylate (oil of wintergreen) from salicylic acid, determining the purity
by gas chromatography. This project helped students appreciate the important
link between molecular structure and properties such as boiling points
and partitioning between solvents.
The FTIR spectra were used to identify simple organic compounds. Students were introduced to the chemistry of several functional groups and strategies for using group IR absorptions to elucidate molecular structure and verify products of reactions. This experience reinforced the link between molecular structure and chemical properties.
NEUROBIOLOGY
PSYC 61 Laboratory in Biopsychology
The HHMI equipment served to give students in this course significant hands-on experience in making measurements that ranged from neurophysiological studies of single cells in a sensory system to compound action potentials recorded from neuromuscular junctions to behavioral responses of the entire organism.
The computerized physiological recording devices were used in various
lab exercises togive the students firsthand experience recording electrophysiological
responses such as the electrocardiogram (EKG), the electromyograph (EMG),
the electroencephalogram (EEG), and evoked potentials (Eps).
The sensory workstations were used to make psychophysical and psychoacoustic measurements in the course exercises while the computers that control the workstations were also used to run software that simulated electrophysiological recording from single neurons in the auditory nerve.
PSYC 98, 99 Independent Study in Psychology
The computerized behavior analysis chambers were used in two student independent research projects investigating (1) the effects of predator odors as natural stressors for rats; and (2) the role of the rat’s vomeronasal system in the detection of pheromones after the rats’ olfactory system had been lesioned with zinc sulfate.
Next year, this equipment will also be used in two new courses currently under development: Introductory Methods in Neuroscience (NEUR 13) and Introductory Methods in Biopsychology (PSYC 2). These introductory methods courses will teach first-year students the basic skills necessary for conducting research in the areas of neuroscience/biopsychology.
PHYSICS
Phys 11, 12 Classical Physics
Students in the elementary physics course used this apparatus to observe the photoelectric effect with accuracy and precision.
Physics 45 Senior Experimental Physics
Physics majors, as well as introductory students in PHYS 11, 12, conducted experiments on gamma-ray spectroscopy, a basic tool of nuclear medidine. Next year this apparatus will also be used for experiments on nuclear detectors and coincidence counting.
2b, 2c. [Not applicable this year.]
In the Molecular Biology program, David Marcey publishes WWW tutorials on macromolecular structure. Creation and use of these tutorials will be enhanced by the new networked workstations for our introductory laboratories. The interactive tutorials, constructed collaboratively by students and faculty, feature visualization of animated molecules that are accompanied by text descriptions of important structure/function relationships. "Hot" buttons in the text elicit changes in the rendering of the molecule to illustrate keypoints. For example, the interactions of non-nucleoside inhibitors (NNI's) of HIV-1 Reverse Transcriptase (RT) with the enzyme are visualized by showing the insertion of an NNI in a hydrophobic binding pocket of RT. Students are able to "get inside" the molecules in these tutorials, and are thus positioned to understand cutting edge advances in macromolecular structure. These tutorials are used in class as striking visual aids, and, more importantly, are accessed by students, at Kenyon and beyond, outside of formal lectures as dramatic learning aids.Our efforts are at the forefront of molecular pedagogy, and our site is one of a handful that use web-based molecular visualization to explore the complex chemistry of macromolecules.
HHMI faculty participant Rosemary Marusak won Kenyon’s Junior Faculty Teaching Award for 1997. Her vision for development of chemistry laboratories formed a major part of our HHMI grant proposal.