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Full-Text Articles in Physiology
Size And Organic Content Of Eggs Of Marine Annelids, And The Underestimation Of Egg Energy Content By Dichromate Oxidation, William Jaeckle, Bruno Pernet
Size And Organic Content Of Eggs Of Marine Annelids, And The Underestimation Of Egg Energy Content By Dichromate Oxidation, William Jaeckle, Bruno Pernet
Scholarship
Dichromate oxidation is a simple technique that is often used to estimate the energy content of eggs in studies of marine invertebrate life histories (1). We used this method to measure the energy contents of the eggs of 12 species of marine annelids. In combination with measures of egg ash-free dry weight (AFDW), these data yielded estimates of AFDW-specific energy density that were mostly lower than the average weight-specific energy density of carbohydrates. This seemed unlikely to be correct, as invertebrate eggs typically contain little carbohydrate and instead are composed primarily of energy-dense protein and lipid (1, 2). After validating …
Variability In Broods Of The Seastar Leptasterias Aequalis, William B. Jaeckle, Brian L. Bingham, Kehualani Giles
Variability In Broods Of The Seastar Leptasterias Aequalis, William B. Jaeckle, Brian L. Bingham, Kehualani Giles
Scholarship
Enormous variation exists in the reproductive output of marine invertebrates (e.g., in the numbers of em¬bryos produced, the volumes of embryos, and the energy that they contain). It is not clear why there is such great variability or what the population-level consequences are. We sampled a population of the brooding seastar Leptasterias aequalis (Stimpson, 1862) to collect basic information on brood sizes, embryo volume, and embryo energy content with a goal to better understand the reproductive ecology of this species. We collected brooding females in February and again in April. We measured the size of their broods and sampled the …
Changes In Gdnf Protein Content Of Skeletal Muscle Following Involuntary Exercise Are Long Lived, Kyle R. Kinnell, Monica J. Czarnopys, John Spitsbergen
Changes In Gdnf Protein Content Of Skeletal Muscle Following Involuntary Exercise Are Long Lived, Kyle R. Kinnell, Monica J. Czarnopys, John Spitsbergen
Biological Sciences Faculty and Graduate Student Research
Glial-cell line derived neurotrophic factor (GDNF) is a neurotrophic factor produced by skeletal muscle. GDNF has been shown to be potent survival factor for motor neurons. We have previously shown that GDNF content in skeletal muscle is altered following exercise and GDNF levels 24 hours after the last bout of exercise are significantly different than those measured immediately after exercise. We sought to determine how long after exercise do GDNF protein levels remain altered. We removed extensor digitorum longus (EDL) and Soleus (SOL), 24 hr, 72 hr and 1 week following the last bout of involuntary exercise. Muscles were processed …
Hatching Asynchrony, Survival, And The Fitness Of Alternative Adult Morphs In Ambystoma Talpoideum, Travis J. Ryan
Hatching Asynchrony, Survival, And The Fitness Of Alternative Adult Morphs In Ambystoma Talpoideum, Travis J. Ryan
Scholarship and Professional Work - LAS
The mole salamander, Ambystoma talpoideum, exhibits both aquatic (gilled) and terrestrial (metamorphosed) adult morphologies. Previous studies have shown the existence of body-size advantages associated with the terrestrial morph in A. talpoideum and other polymorphic salamanders (e.g., A. tigrinum). However, aquatic adult A. talpoideum mature at a younger age and often breed earlier than terrestrial adults. We tested the hypothesis that early maturation and reproduction in aquatic adults increase fitness (irrespective of body size). We reared larval A. talpoideum in mesocosms and varied the timing of hatching, with early-hatching larvae representing the offspring from early-breeding aquatic adults, and late-hatching larvae representing …