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Full-Text Articles in Biology

Effects Of Short Shoot Number And Presence Of An Apical Meristem On Rhizome Elongation, New Short Shoot Production, And New Rhizome Meristem Production Of Thalassia Testudinum Banks And Solander Ex König Planting Units In Tampa Bay., Michael Vearl Meads Jul 2012

Effects Of Short Shoot Number And Presence Of An Apical Meristem On Rhizome Elongation, New Short Shoot Production, And New Rhizome Meristem Production Of Thalassia Testudinum Banks And Solander Ex König Planting Units In Tampa Bay., Michael Vearl Meads

USF Tampa Graduate Theses and Dissertations

Thalassia testudinum Banks and Solander ex König is the dominant seagrass in the Gulf of Mexico, Caribbean and the West Coast of Florida, yet little rhizome elongation, new short shoot production, or new rhizome meristem production data has been collected via direct measurement. A study of the rhizome growth of T. testudinum was completed in December 2004 in southern Tampa Bay that determined growth after 26.5 months. Two PVC planting frames each containing four rhizomes with 2 short shoots, two rhizomes with 4 short shoots, and two rhizomes with 8 short shoots were planted next to existing T. testudinum beds …


Reproductive Biology Of The Southern Dwarf Siren, Pseudobranchus Axanthus, In Southern Florida, Zachary Cole Adcock Jul 2012

Reproductive Biology Of The Southern Dwarf Siren, Pseudobranchus Axanthus, In Southern Florida, Zachary Cole Adcock

USF Tampa Graduate Theses and Dissertations

The salamander family Sirenidae is composed of two extant genera, Siren and Pseudobranchus, each with two known species. Several questions regarding Sirenidae life history persist, and much of the available life history data for Pseudobranchus are attributed to studies of P. axanthus in northern Florida. Information on the reproductive biology of P. axanthus is limited, and historical references often suggest contradictory results. This study was undertaken to clarify information and expand on the limited data regarding P. axanthus reproductive biology, specifically for southern Florida populations. The study population was most likely the P. a. belli subspecies. P. axanthus in southern …


Availability And Quality Of Vegetation Affects Reproduction Of The Gopher Tortoise (Gopherus Polyphemus) In Improved Pastures, Anna Louise Hathaway Jun 2012

Availability And Quality Of Vegetation Affects Reproduction Of The Gopher Tortoise (Gopherus Polyphemus) In Improved Pastures, Anna Louise Hathaway

USF Tampa Graduate Theses and Dissertations

As part of a state-funded Gopher Tortoise (Gopherus polyphemus Daudin) translocation project, I monitored actively grazed improved pastures to determine if they could serve as suitable recipient sites for the threatened Gopher Tortoise displaced by human development. For cattle ranches to be considered suitable recipient sites females must be able to acquire sufficient energy to produce a clutch of viable eggs, and sufficiently high quality vegetation must be available to support juvenile recruitment into the population. Vegetation surveys were conducted to determine the composition and percent cover of plant species, especially those containing high amounts of nutrients, specifically nitrogen. Resident …


A Study Of The Eastern Oyster, Crassostrea Virginica, In Tampa Bay: Effects Of Perkinsus Marinus On Reproduction And Condition, Bridgit Melora Mccrickard Jun 2012

A Study Of The Eastern Oyster, Crassostrea Virginica, In Tampa Bay: Effects Of Perkinsus Marinus On Reproduction And Condition, Bridgit Melora Mccrickard

USF Tampa Graduate Theses and Dissertations

Abstract

Five sites in Tampa Bay, Florida, were sampled monthly from February 2006 to January 2007. These sites were located at the mouth of the Alafia River, in an inlet of Cross Bayou, on the easement of Gandy Bridge, near mangrove in Manatee County, and an inlet of Salt Creek, off Bayboro Harbor. Standard methods were used to determine shell height and Condition Index (CI). Intensity and prevalence of Perkinsus marinus were analyzed using Ray's Thioglycollate medium test, while Haplosporidium nelsoni was studied by histological examination. Histological methods were also used to determine sex ratios, reproductive phases, and egg diameters. …


Dissolved Inorganic Carbon Uptake In Thiomicrospira Crunogena Xcl–2 Is Atp–Sensitive And Enhances Rubisco–Mediated Carbon Fixation, Kristy Jae Menning May 2012

Dissolved Inorganic Carbon Uptake In Thiomicrospira Crunogena Xcl–2 Is Atp–Sensitive And Enhances Rubisco–Mediated Carbon Fixation, Kristy Jae Menning

USF Tampa Graduate Theses and Dissertations

Many autotrophic organisms living in environments with episodically low dissolved inorganic carbon (DIC) concentrations compensate for these fluctuations by employing a carbon concentrating mechanism (CCM). By utilizing a CCM, these organisms can generate intracellular DIC concentrations much higher than extracellular, thereby providing sufficient substrate for carbon fixation. Carbon concentrating mechanisms have been well-studied in cyanobacteria but studies are lacking in other autotrophs. The gammaproteobacterium Thiomicrospira crunogena XCL-2 is a hydrothermal vent chemolithoautotroph that has a CCM, which is functionally similar to that of cyanobacteria. At hydrothermal vents, DIC concentrations and pH values fluctuate over time, with CO2 concentrations ranging from …


Social Organization And Decision Making In North American Bison: Implications For Management, Ryan A. Shaw May 2012

Social Organization And Decision Making In North American Bison: Implications For Management, Ryan A. Shaw

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Social organization varies widely among herbivores, and the level of social organization in bison is widely debated. I hypothesized that when mother-daughter relationships are allowed to develop, bison form long-term associations. In my study, 25 treatment mothers were selected from a free-ranging herd and kept together with their calves, while 25 control females had their calves forcefully removed. Treatment mothers and offspring had by far the greatest number of associations with a greater percentage of individuals with a half weight index (HWI) > 0.50. The strongest associations (HWI > 0.31) were among treatment mothers and their offspring. Moreover, these associations persisted over …


Plant Species Richness And Species Area Relationships In A Florida Sandhill, Monica Ruth Downer Mar 2012

Plant Species Richness And Species Area Relationships In A Florida Sandhill, Monica Ruth Downer

USF Tampa Graduate Theses and Dissertations

Pine sandhill are integral pyrogenic communities in the southeastern United States. Though once widespread, habitat destruction, fire suppression and fragmentation have reduced the population to nearly 3%. It is important to learn as much as possible about these unique areas in order to implement best management practices to conserve and restore the existing populations of these communities.

Fire is central to the maintenance of pine sandhill communities and two conceptual hypothesis regarding burn frequency have come to light in maintaining the unique species composition and richness of these areas. The first is the Intermediate Disturbance Hypothesis which suggests that intermediate …


Assessing The Link Between Coastal Development And The Quality Of Fish Habitat In Mangrove Tidal Tributaries, Justin Micheal Krebs Mar 2012

Assessing The Link Between Coastal Development And The Quality Of Fish Habitat In Mangrove Tidal Tributaries, Justin Micheal Krebs

USF Tampa Graduate Theses and Dissertations

To assess the potential influence of coastal development on the quality of estuarine habitat for nekton, we characterized land use and the intensity of land development surrounding small tidal tributaries of Tampa Bay. Based on this characterization, we classified tributaries as undeveloped, industrial, urban or man-made (i.e., mosquito-control ditches). Over one-third (37%) of tributaries were determined to be heavily developed, while fewer than one-third (28%) remain relatively undeveloped. We then examined the nekton community from eleven tributaries in watersheds representing the defined land-use classes. Whereas mean nekton density and species richness were both independent of land use, nekton-community structure differed …


Matrix Metalloproteinase Genes Are Transcriptionally Regulated By E2f Transcription Factors: A Link Between Cell Cycle Control And Metastatic Progression, Jacqueline Lea Johnson Feb 2012

Matrix Metalloproteinase Genes Are Transcriptionally Regulated By E2f Transcription Factors: A Link Between Cell Cycle Control And Metastatic Progression, Jacqueline Lea Johnson

USF Tampa Graduate Theses and Dissertations

The RbµE2F transcriptional regulatory pathway plays a critical role in the cell cycle. Rb is inactivated through multiple waves of phosphorylation, mediated mainly by cyclin D and cyclin E associated kinases. Once Rb is inactivated, cells can enter Sµphase. Collectively, three Rb family members and ten E2F proteins coordinate every additional stage of the cell cycle, from quiescence to mitosis. However the RbµE2F pathway is frequently altered in cancer. Aside from cell proliferation, the RbµE2F pathway regulates other essential cellular processes including apoptosis, cell differentiation, angiogenesis and DNA damage repair pathways, but its role in invasion and cancer progression is …


Consequences Of Kleptoplasty On The Distribution, Ecology, And Behavior Of The Sacoglossan Sea Slug, Elysia Clarki, Michael Louis Middlebrooks Jan 2012

Consequences Of Kleptoplasty On The Distribution, Ecology, And Behavior Of The Sacoglossan Sea Slug, Elysia Clarki, Michael Louis Middlebrooks

USF Tampa Graduate Theses and Dissertations

The sacoglossan sea slug Elysia clarki is able to photosynthesize for three to four months using chloroplasts sequestered from its algal food sources. Furthermore, the slug is able to store multiple chloroplasts from different algal species within the same cell. This research, consisting of several related studies, explores the role that provision of organic nutrients via photosynthesis plays in the biology of the slug. The first chapter demonstrates that, under conditions of starvation, photosynthetic activity in E. clarki remains fully functional for one month after which it then declines. During the first month of starvation the slug exhibits similar feeding …


Use Of Adventitious Roots For The Determination Of Hydroperiod In Isolated Wetlands, Michael Joseph Reyes Jan 2012

Use Of Adventitious Roots For The Determination Of Hydroperiod In Isolated Wetlands, Michael Joseph Reyes

USF Tampa Graduate Theses and Dissertations

Abstract

Accurate measurement of the hydroperiod in isolated wetlands currently relies upon the installation and frequent monitoring of devices such as piezometers and staff gauges. Observations of biological indicators of the hydroperiod may be able to supplement data collected from these devices and could potentially replace them as a means of accurately determining this hydrologic interval. The study objective was to determine whether adventitious root formation and maturation on buttonbush (Cephalanthus occidentalis) could be used as a viable indicator of the hydroperiod in isolated wetlands. Buttonbush seedlings were flooded in a controlled environment over a three month period in the …