. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. FIGURE 9. A. Intracellular recording from Type B photoreceptor (upper trace) and caudal hair cell (lower trace) in a preparation containing a single statoconium. Single trace at the bottom illustrates the time course of the rotational stimulus demonstrating the absence of a generator potential in response to rotation (g = ). B. Synaptic inhibition and hyperpolarization of Type B photoreceptors resulting from an electrically produced firing burst in a caudal hair cell preparation with typical number of statoconia. C. Synap
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. FIGURE 9. A. Intracellular recording from Type B photoreceptor (upper trace) and caudal hair cell (lower trace) in a preparation containing a single statoconium. Single trace at the bottom illustrates the time course of the rotational stimulus demonstrating the absence of a generator potential in response to rotation (g = ). B. Synaptic inhibition and hyperpolarization of Type B photoreceptors resulting from an electrically produced firing burst in a caudal hair cell preparation with typical number of statoconia. C. Synaptic inhibition of a Type B photoreceptor resulting from electrical stimulation of an ipsilateral caudal hair cell in a statocyst containing a single statoconium. DISCUSSION Although antibiotics are used routinely to control bacterial populations in marine invertebrate culture systems (Smith and Chanley, 1972), little is known about their physiological effect on growth and morphology of the developing animal. Biochemical investigations have shown that both chloramphenicol and rifampicin inhibit protein synthesis in eukaryotes (Corcoran and Hahn, 1975). These antibiotics, used in the present study at 5 /ig/ml each, inhibited the post-metamorphic growth rate of Her- missenda relative to growth rates in the absence of antibiotic. Both antibiotics were applied within the reported concentration range for effects on eukaryotic systems (Corcoran and Hahn, 1975). Antibiotic-induced inhibition of growth rate was the only variable that was sig- nificantly related to the number of statoconia per statocyst. With few exceptions, the slowest-growing animals possessed statocysts containing a single statoconium. Because three out of eleven animals maintained in the absence of antibiotics contained a single statoconium in each statocyst, and because a similar sample of very small ( Please note that these images are extracted from scanned page images that may have been digitally enhanced
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
