Dissertations and Theses @ UNI


Open Access Thesis


Bullfrog--Hibernation; Mitosis--Regulation; Blood plasma;


Hibernation is a process that occurs in nature where organisms undergo dormancy for long periods of time in order to improve their survival during extreme environmental conditions. During this time, organisms undergo physiological changes such as reduction in core body temperature and metabolic rate, as well as cells being impeded from going into mitosis. Alvarado et al. (2015) discovered that genomic DNA methylation is dynamic across torpor-arousal bouts during winter hibernation in thirteen lined ground squirrels (Ictidomys tridecemlineatus), indicating that physiological changes during hibernation are the results of more than simply cold temperatures slowing down metabolism and that there are cellular mechanisms that are responsible for such physiological changes. A study by Robbins (2017) found that THP-1 cells incubated in hibernating bullfrog plasma (Lithobates catesbeianus) stop undergoing cellular division, with THP-1 cells being restricted to the G2 stage of the cell cycle. This suggests that there may be one or more substances in hibernating bullfrog plasma that prevent THP-1 cells from progressing in cell division. In this study, I explored the effects of cyclin B levels on cellular division and its potential impact on confining THP-1 cells in the G2 phase, while maintained in hibernating bullfrog plasma. My results indicate that the levels of cyclin B in hibernating and non-hibernating bullfrog plasma do not vary, suggesting that the expression of cyclin B may not be responsible for confining THP-1 cells to the G2 stage of the cell cycle.

Year of Submission


Degree Name

Master of Science


Department of Biology

First Advisor

David Saunders, Chair, Thesis Committee

Date Original


Object Description

1 PDF file (vi, 44 pages)



File Format


Included in

Biology Commons