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Mechanism of the Diastole of Contractile Vacuoles
Nature, 1937IT is still not known what causes the passage of fluid from the cytoplasm into the contractile vacuole of a protozoan. In a recently published paper1, Picken has claimed that the rate of this ” infiltration” of fluid into the vacuole will be proportional, among other things, to the difference between the hydrostatic pressure of the cytoplasm (which is ...
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The contractile vacuole of paramecium multimicronucleata
Journal of Morphology, 1935AbstractEach contractile vacuole system of Paramecium multimicronucleata is made up of a number of components, some temporary and others permanent. The contracting vacuole with its membrane is a temporary structure as are the vesicles which fuse to form it. The vacuole discharges its contents to the exterior leaving a vestige closing the pore. The pore,
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The Physiology of Contractile Vacuoles
Journal of Experimental Biology, 1960ABSTRACT The suctorian Discophrya collini (Root) has been subjected to D2O–H2O mixtures containing up to 99·7 % D2O. In 25 % D2O or over there is a rapid but temporary shrinkage of the body. This shrinkage is difficult to estimate owing to the wrinkling of the body surface, but amounts to at least 10% in the undiluted (99.7%) D2O. During
J. E. Padfield +2 more
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The Contractile Vacuole in Amoeba proteus: Temperature Effects
The Journal of Protozoology, 1974SYNOPSISThe influence of temperature on the various aspects of the contractile vacuole cycle of Amoeba proteus has been established. In the upper temperature range (20, 25 and 30 C) an increase in temperature results in shorter vacuolar cycles with greater systolic (final) volumes. The systole is rapid and always complete. At 35 C the vacuole shows the
Mukhtar Ahmad, Pierre Couillard
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The formation of contractile vacuoles in Amoeba proteus
Journal of Morphology, 1927AbstractThe history of investigations on the contractile vacuole is reviewed briefly and brought up to date.The study of the contractile vacuole in Amoeba proteus is considered from standpoints of origin, structure, behavior, and function. The results are obtained from a prolonged study of normal organisms and from their reactions when introduced into ...
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ATP and the autonomy of the contractile vacuole in Amoeba proteus
Journal of Experimental Zoology, 1984AbstractContractile vacuole function in amoebae treated with immobilizing (5 mM) and nonimmobilizing (0.125 mM) concentrations of ATP has been studied. In ATP‐immobilized amoebae, most vacuolar parameters are accelerated, especially the rate of output which passes from 30 to 70 μm3/sec. This favors the concept of an autonomous vacuole, fully functional
Pierre Couillard, F. Pothier, J. Forget
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Amoeba proteus : Studying the Contractile Vacuole by Micropuncture
Science, 1963Direct measurements of the freezing point depression of the protoplasm and of the fluid from the contractile vacuole of fresh-water amoebae showed that the fluid in the vacuole is distinctly hypoosmotic to the protoplasm. Fourteen samples of protoplasm from amoebae, placed in a medium with a milliosmolality of 7, had an average osmolality of 101 ...
Bodil Schmidt-Nielsen +1 more
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Fine Structure of the Contractile Vacuole Pore in Paramecium*
The Journal of Protozoology, 1973SYNOPSISThe pore through which a Paramecium contractile vacuole communicates with the external environment is a 1.2 μm long and 1 μm diameter cylindrical orifice in the pellicle. During diastole, the vacuole:pore junction is closed by a substantial diaphragm which parts to the side at systole.
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Activity of contractile vacuole in the parasitic ciliate,Balantidium coli
Experientia, 1970Chez leBalantidium coli, la vacuole contractile se remplit graduellement et s'agrandit. Apres une phase stationnaire, pendant laquelle elle reste irreguliere en apparence, elle se gonfle entierement, devient spherique, et puis s'affaisse subitement et expulse son contenu. L'affaissement est tres rapide et ne prend qu'une fraction de seconde.
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The Role of the Contractile Vacuole in the Osmoregulation of Tetrahymena pyriformis*
The Journal of Protozoology, 1973SYNOPSISThe relationship of cell size and contractile vacuole efflux to osmotic stress was studied in Tetrahymena pyriformis strain W, after transfer into fresh solutions iso‐ or hypoosmotic to the growth medium. Microscopic measurements of the cell and contractile vacuole dimensions, made with an image‐sharing ocular at 27 C, allowed the calculation ...
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