Ciliary Reversal of Paramecium
نویسندگان
چکیده
منابع مشابه
Ciliary Motion in Paramecium
The scanning electron microscope (SEM) provides an ideal system for studying the three-dimensional surface structure of biological materials . Our previous work on the protozoan Opalina showed that instantaneous fixation, combined with critical point drying, faithfully preserved the pattern of ciliary coordination and the form of ciliary beat for scanning electron microscopy (1, 2) . I report h...
متن کاملRegulation of ciliary reversal in triton-extracted Paramecium by calcium and cyclic adenosine monophosphate.
A Triton-extracted model of Paramecium swims forwards when the Ca2+ concentration in the reactivation medium containing ATP is below 10(-6) M and swims backwards when Ca2+ concentration is above 10(-6) M. We found that cAMP (adenosine 3':5'-cyclic monophosphoric acid) inhibited Ca-induced backward swimming of the model and caused forward swimming even when the [Ca2+] was above 10(-6) M. This ef...
متن کاملDifferential regulation of Paramecium ciliary motility by cAMP and cGMP
cAMP and cGMP had distinct effects on the regulation of ciliary motility in Paramecium. Using detergent-permeabilized cells reactivated to swim with MgATP, we observed effects of cyclic nucleotides and interactions with Ca2+ on the swimming speed and direction of reactivated cells. Both cAMP and cGMP increased forward swimming speed two- to threefold with similar half-maximal concentrations nea...
متن کاملPassive Electrical Properties of Paramecium and Problems of Ciliary Coordination
Potential recordings made simultaneously from opposite ends of the cell indicate that the cytoplasmic compartment of P. caudatum is nearly isopotential. Measured decrements of the spread of steady-state potentials are in essential agreement with calculated decrements for a short cable model of similar dimensions and electrical constants. Action potentials and passively conducted pulses spread a...
متن کاملElectrophysiological Control of Reversed Ciliary Beating in Paramecium
Quantitative relations between ciliary reversal and membrane responses were examined in electrically stimulated paramecia. Specimens bathed in 1 mM CaCl(2), 1 mM KCl, and 1 mM Tris-HCl, pH 7.2, were filmed at 250 frames per second while depolarizing current pulses were injected. At current intensities producing only electrotonic shifts the cilia failed to respond. Stimuli which elicited a regen...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Proceedings of the Imperial Academy
سال: 1940
ISSN: 0369-9846,1881-1140
DOI: 10.2183/pjab1912.16.241