This exercise is designed to introduce students to chemiosmotic principles of solute transport. Periplaneta americana , spectrophotometry, uric acid. This exercise enables students to gain insight into the process of excretion in insects. Rate of excretion and hemolymph volume in the migratory locust, Locusta migratoria, are measured using spectrophotometry. The capacity of two insects, the cockroach, Periplaneta americana, and L. migratoria , to detoxify ammonia via uricotelism is examined by measuring the concentration of uric acid in the insects' hemolymph and feces.
Uric acid is quantified by ultraviolet spectrophotometry.
The anatomy of the insect's excretory system is studied by dissection. The sex pheromone is then assayed quantitatively and employed in experiments on male orientation and male and female interactions in courtship behavior. Eight simple enzyme experiments are described. Materials which are easy to obtain, inexpensive, and familiar to most students are stressed. Enzymes included are amylase, catalase, catecholase, invertase, papain, pectinase, pepsin, and rennin.