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Examining The Effects Of Fadrozole, An Aromatase Inhibitor, On Testosterone And Estrogen Production Of Domestic Chicken Embryos (Gallus Gallus), Abby E. Joseph
Examining The Effects Of Fadrozole, An Aromatase Inhibitor, On Testosterone And Estrogen Production Of Domestic Chicken Embryos (Gallus Gallus), Abby E. Joseph
Honors Theses
The hypothalamic-pituitary-gonadal (HPG) axis is responsible for the production of the hormones testosterone and estradiol, and testosterone is thought to contribute to regulation of the axis through a negative feedback mechanism. Regulation by negative feedback involves the product of a pathway turning off that pathway when enough product is made. However, because the enzyme P450 aromatase converts testosterone to estradiol, estradiol may also contribute to regulation of the HPG axis and other phenomena that have been attributed to testosterone, like the inhibition of immune function. Previous studies have injected birds with an aromatase inhibitor (presumably reducing estradiol production) and shown …
Evidence Of A Rudimentary Colon In Leucoraja Erinacea, Alyssa M. Simeone
Evidence Of A Rudimentary Colon In Leucoraja Erinacea, Alyssa M. Simeone
Honors Theses
During the transition of animals from water onto land, the colon is believed to have evolved as an essential water-absorbing organ in terrestrial vertebrates to prevent desiccation. The class Chondrichthyes, comprised of sharks, rays, and skates, are isotonic to their marine environment, and thus do not require a functional colon. The Chondrichthyes are an excellent organism for developmental and physiological studies in evolutionary context because they have undergone little evolutionary change since their appearance 450 million years ago. Previous histochemical studies demonstrate potential water absorbing properties in the digestive tract of the little skate, Leucoraja erinacea (Theodosiou et al., 2007). …
The Exploration Of Novel Symbiotic Bacteria That May Have Influential Roles In Sponge Life History, Brittany E. West
The Exploration Of Novel Symbiotic Bacteria That May Have Influential Roles In Sponge Life History, Brittany E. West
Honors Theses
Sponges produce an impressive variety of secondary metabolites that perform a variety of ecological functions. Many marine sponges even harbor diverse carotenoid compounds, an unusual class of secondary metabolites that animals are incapable of producing. Furthermore, sponges serve as hosts to an astonishingly diverse microbial community that can occupy up to sixty percent of a sponge's biomass. Our research ultimately hopes to link microbial species to the production of secondary compounds, like carotenoids, and to assess the ecological role of such compounds and their effect on sponge life history strategy. This study describes the ecological distribution of two species of …
The Effects Of Thyroid Hormone On Myosin Heavy Chain A-7 Production In Xenopus Laevis Tail And Leg Muscles, Andrew R. Noble
The Effects Of Thyroid Hormone On Myosin Heavy Chain A-7 Production In Xenopus Laevis Tail And Leg Muscles, Andrew R. Noble
Honors Theses
The present research examines the expression of myosin heavy chain genes in muscle fibers in Xenopus laevis. Characteristically different muscle fibers are expressed before and after metamorphosis. The embryonic myosin proteins that are synthesized during the tadpole stages are replaced with adult myosin heavy chains at metamorphosis. At least one of the adult myosin genes, called A-7, is expressed only in the adult animals, not in tadpoles. The controlling factor or trigger for the expression of this adult gene still remains unknown. There are a number of possible explanations for the A-7 regulation at metamorphosis, including changes in particular hormone …