Elizabeth Bowdan

Learn More
The interactions of excitatory and inhibitory neural input controlling feeding behaviours of fliesPhormia regina Meigen, at three different levels of deprivation were assessed by studying the proboscis extension reflex, volume of sucrose imbibed and the responsiveness of the contact chemosensory neurons. The responsiveness of the sensory cells tested did(More)
Follicle cells were removed by dissection from early vitellogenic oocytes of the cockroach Blattella germanica. The vibrating probe was used to record steady currents from 19 defolliculated oocytes and 19 intact follicles of the same developmental stage. Defolliculated oocytes generated currents that were stable and distinguishable (by intensity or(More)
The development of patterns of current around vitellogenic oocytes of the cockroach, Blattella germanica, was examined by means of a two-dimensional vibrating probe. Previtellogenic oocytes exhibited small unstable currents. Shortly after vitellogenic uptake began (oocytes 0.6-0.8 mm anterior to posterior) currents were either all inward or all outward at(More)
1. Extracellular and intracellular recordings were made from the five main muscles moving the mesothoracic leg; where possible the movement of the leg was simultaneously monitored. 2. During slow leg retraction muscle activity is very variable. 3. During rapid leg retraction (the power portion of the rowing stroke) the four muscles which retract and rotate(More)
The responses of contact chemosensory sensilla on the tarsi of the apple maggot fly,Rhagoletis pomonella (Walsh), to a range of concentrations of salt, sucrose and oviposition-deterrent pheromone were studied (Fig. 1). Examination of dose-response curves (Fig. 2), short- and long-term adaptation (Figs. 3+4, Table 1) and impulse height and duration (Fig. 5,(More)
Regulation of feeding is a fundamental element of homeostasis. This is reflected in the similarity of control mechanisms in a wide range of animals, including insects and humans. A close examination of feeding behavior can illuminate the physiological processes driving regulation. A simple, inexpensive method for recording fine details of feeding by(More)
An automated device was used to examine, in detail, feeding on disks of wheat germ medium by fifth-instar Manduca sextacaterpillars. Comparisons were made between some animals which had ad libitum access to food at all times and others which were deprived of food for 1–5 h before being tested. Feeding patterns of both groups indicated regulation of feeding(More)
An insect oocyte with a disc-shaped sink of current on its ventral surface during a vitellogenic phase of development is used to demonstrate modeling of expected currents arising from a mathematically defined source. A simple model with an analytical solution for the expected currents is compared to a more complex model in which expectations are computed by(More)
  • 1