Biology Commons^™

The Toxicity Of Cadmium To The Aquatic Amphibian, Xenopus Laevis, Sharon S. Millirons

Master's Theses

Cadmium toxicity is poorly understood but is a potentially serious environmental pollutant. This study was initiated to determine the effect of significant concentrations of cadmium on a readily available aquatic laboratory organism.

The lethal concentration (LC50) for 50 percent of I week old Xenopus laevis tadpoles was determined to be 0.1 ppm CdCI 2. For 5 week old animals, the average LC50 was determined to be 0.98 ppm. Thus, cadmium poses greater toxic threats to the early developmental stages. Moreover, these concentrations of cadmium exceed those commonly found in the nation's water supply. Histological examination suggested that the main site …

Investigation Of Different Patterns Of Induction Of Amylases In Different Cultivars Of Rice, Oryza Sativa L., Angela M. Mosley

Master's Theses

This study investigated whether rice exhibits exceptions to the accepted model, in cereals, for the induction of a and P-amylase in the embryo and endosperm during germination. We also tried to establish whether different patterns of induction were cultivar specific, or due to the influence of ripening temperature, or a component of the incubation medium. An isoelectric focusing technique was used to monitor a- and P-amylase activities, a spectrophotometric assay was used to quantify the activity of a-amylase, and two cDNA clones, RAmy3D and RAmylA, were used to measure a-amylase RNA accumulation by Northern analysis. Distinct patterns of induction of …