Another difference is that sun leaves are thicker, having extra layers of photosynthetic cells to absorb direct sunlight. In this exercise, students quantify these differences in shape and thickness. Monoclonal antitubulin antibodies produced in mice will be used to label bull sperm microtubules and the location of these antibodies will be determined by use of a peroxidase conjugated secondary antibody and the DAB staining reaction. The Malpighian tubules of insects are an excellent model for examining the properties of secretion in a transporting epithelium. In this exercise students expose tubules from cockroaches or crickets to chlorophenol red and visually estimate the dye concentration in the lumen.
Advanced students can design their own experiments after a review of the literature.
This simple and inexpensive exercise provides students with a challenging and rewarding introduction to experimental design in the laboratory. One program simulates passive conduction in a long length of axon while the second program simulates the Hodgkin-Huxley equations for the production of an action potential. This enables one to see how neurons of different physical characteristics differ in their electrical behavior. This laboratory is suitable for students of varying backgrounds. The venom of the honeybee, Apis mellifera , contains numerous enzymes, volatiles, and other components.