Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 5 of 5
Full-Text Articles in Life Sciences
Conservation Implications Of The Reproductive Biology Of The Endangered Vine Ipomoea Microdactyla Griseb. (Convolvulaceae), John H. Geiger
Conservation Implications Of The Reproductive Biology Of The Endangered Vine Ipomoea Microdactyla Griseb. (Convolvulaceae), John H. Geiger
FIU Electronic Theses and Dissertations
A plant’s reproductive biology exerts a significant influence on both population persistence within changing environments and successful establishment of new populations. However, the interaction between extrinsic (i.e. ecological) and intrinsic (i.e. genetic) factors also is an important driver of demographic performance for plant populations. It is light of this that I performed a multidisciplinary investigation of the breeding system, seed and seedling establishment dynamics, and population genetic structure of the endangered Caribbean vine Ipomoea microdactyla Griseb. (Convolvulaceae). The results from the breeding system study show individuals from Florida, USA and Andros Island, Bahamas to be self-incompatible. Plants from the two …
Effects Of A Short-Term Freeze On Sphagnum Girgensohnii Grown Under Different Light-Temperature Regimes, Jane Sarah Colby
Effects Of A Short-Term Freeze On Sphagnum Girgensohnii Grown Under Different Light-Temperature Regimes, Jane Sarah Colby
FIU Electronic Theses and Dissertations
During the short, snow-free growing seasons in the Arctic, sudden “cold snaps” or freeze thaw events (FTE) frequently occur when temperatures fall subzero for 24 to 72 h. Vascular plants exposed to FTE are often irreversibly damaged, but despite their importance, the responses of nonvascular plants to FTE have been little studied. I grew plants of Sphagnum girgensonhii under high and low light and temperature conditions to investigate whether pre-freeze conditions influence damage and recovery of this important moss species. Plants grown at low light and high temperature showed the greatest growth. Upon freezing they also showed irreversible physiological damage …
Morphology And Anatomy Of Three Common Everglades Utricularia Species; U. Gibba, U. Cornuta, And U. Subulata, Theresa A. Meis Chormanski
Morphology And Anatomy Of Three Common Everglades Utricularia Species; U. Gibba, U. Cornuta, And U. Subulata, Theresa A. Meis Chormanski
FIU Electronic Theses and Dissertations
Members of the aquatic plant genus Utricularia exhibit many unique characteristics: nutritional supplementation carried out by the most complex trapping mechanism of any carnivorous plant, extremely modified vegetative morphology, relaxed developmental constraints, high generic diversity, and fast genomic substitution rates. The vegetative morphology, anatomy and growth pattern of three species common to Florida's Everglades, U. gibba, U. cornuta, and U. subulata were analyzed in depth. Specimens were collected from different habitats in South Florida during both the wet and dry seasons. Light and scanning electron microscopy were used to quantify anatomical and morphological characteristics. A morphological model describing …
Groundwater Nutrient Availability Controls On Nearshore Benthic Community Structure In Biscayne Bay, Florida, Danielle Lara Mir-Gonzalez
Groundwater Nutrient Availability Controls On Nearshore Benthic Community Structure In Biscayne Bay, Florida, Danielle Lara Mir-Gonzalez
FIU Electronic Theses and Dissertations
Most studies have focused on nutrient inputs from rivers, atmosphere, and nonpoint runoff. One often overlooked source of nutrient loading is submarine groundwater discharge. For this reason, a 207 site survey and four transects were established to document spatial distribution of macrophytes, quantify potential groundwater discharge and associated nutrient concentrations, estimate water column nutrient concentrations, and relate nutrient availability to seagrass stoichiometry. A significant decline in Thalassia testudinum and an associated increase in Halodule wrightii were significantly correlated with decreased salinity and increased ammonium and total phosphorus concentrations from surface and groundwater. Total phosphorus loading from groundwater was estimated to …
Neuroendocrine Control Of A Dynamic Communication Signal, Susan J. Allee
Neuroendocrine Control Of A Dynamic Communication Signal, Susan J. Allee
FIU Electronic Theses and Dissertations
Multiple physiological systems regulate the electric communication signal of the weakly electric gymnotiform fish, Brachyhypopomuspinnicaudatus. Fish were injected with neuroendocrine probes which identified pharmacologically relevant serotonin (5-HT) receptors similar to the mammalian 5-HT1AR and 5-HT2AR. Peptide hormones of the hypothalamic-pituitary-adrenal/interrenal axis also augment the electric waveform. These results indicate that the central serotonergic system interacts with the hypothalamic-pituitaryinterrenal system to regulate communication signals in this species. The same neuroendocrine probes were tested in females before and after introducing androgens to examine the relationship between sex steroid hormones, the serotonergic system, melanocortin peptides, and EOD modulations. Androgens caused an increase in …