Award Date


Degree Type


Degree Name

Master of Science (MS)


Biological Science

First Committee Member

Karin Hoff

Number of Pages



Toads hydrate from standing water or moist substrates by osmotic absorbtion across the ventral skin. On land toads adopt a distinctive posture called the water absorption response (WR) to maximize contact with the substrate and facilitate water absorption. Experiments using hydration behavior on moist substrates and rehydration rate in standing water or salt solutions in dehydrated Red-spotted toads (Bufo punctatus) were used to demonstrate that: (1) toads can distinguish among NaCl concentrations, (2) NaCl facilitates water uptake across the skin, and (3) transport of the chloride anion facilitates sodium uptake and affects sodium detection by the toad. The results of these studies also strongly suggest that general osmotic mechanisms as well as epithelial sodium channels function in chemosensation across the amphibian skin and that the ventral skin and the feet may have different roles in chemosensation.


Behavior; Bufo; Chloride; Concentration; Effects; Gluconate; Hydration; Punctatus; Red; Sodium; Spotted; Toad; Transport; Water; Watertransport

Controlled Subject


File Format


File Size

1280 KB

Degree Grantor

University of Nevada, Las Vegas


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