Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 3 of 3
Full-Text Articles in Physiology
Energetic Cost And Physiological Trade-Offs, Heba A. Ali
Energetic Cost And Physiological Trade-Offs, Heba A. Ali
FIU Electronic Theses and Dissertations
Understanding how organisms allocate limited resources across physiological systems is a major challenge in biology. This study revealed that high energetic demand of electric signals of male electric fish (Brachyhypopomus gauderio) is matched by a metabolic trade-off with other cellular functions. We used thyroxine (T4) to modulate the fish’s signal metabolism, partitioned the energy budget pharmacologically, and measured energy consumption using oxygen respirometry. In males, total energy consumption was unchanged pre- and post-T4 treatment, while signal metabolism rose and the standard metabolic rate fell in an even trade-off. Total metabolism in females did the opposite. Under T4, the …
Regulation Of Juvenile Hormone Synthesis By 20-Hydroxyecdysone In The Yellow-Fever Mosquito, Aedes Aegypti, Maria Areiza
Regulation Of Juvenile Hormone Synthesis By 20-Hydroxyecdysone In The Yellow-Fever Mosquito, Aedes Aegypti, Maria Areiza
FIU Electronic Theses and Dissertations
In Aedes aegypti, development and reproduction are regulated by juvenile hormone III (JH). This master regulatory hormone is synthesized by the corpora allata (CA), a pair of endocrine glands with neural connections to the brain. JH titers are largely determined by the rate of biosynthetic activity of the CA and are regulated by inhibitory and stimulatory factors. Like JH, the ecdysteroid 20-hydroxyecdysone (20E) is a key hormonal regulator and has been proposed as an allatoregulator in other insects. However, its part in the regulation of JH biosynthesis of mosquitoes was unknown. The specific aims of this dissertation were to …
The Effect Of Male-Male Competition And Its Underlying Regulatory Mechanisms On The Electric Signal Of The Gymnotiform Fish Brachyhypopomus Gauderio, Vielka Lineth Salazar
The Effect Of Male-Male Competition And Its Underlying Regulatory Mechanisms On The Electric Signal Of The Gymnotiform Fish Brachyhypopomus Gauderio, Vielka Lineth Salazar
FIU Electronic Theses and Dissertations
Sexually-selected communication signals can be used by competing males to settle contests without incurring the costs of fighting. The ability to dynamically regulate the signal in a context-dependent manner can further minimize the costs of male aggressive interactions. Such is the case in the gymnotiform fish Brachyhypopomus gauderio, which, by coupling its electric organ discharge (EOD) waveform to endocrine systems with circadian, seasonal, and behavioral drivers, can regulate its signal to derive the greatest reproductive benefit. My dissertation research examined the functional role of the EOD plasticity observed in male B. gauderio and the physiological mechanisms that regulate the enhanced …