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Osmoregulation and contractile vacuoles of protozoa
2002Protozoa living in fresh water are subjected to a hypotonic environment. Water flows across their plasma membrane since their cytosol is always hypertonic to the environment. Many wall-less protozoa have an organelle, the contractile vacuole complex (CVC), that collects and expels excess water.
Richard D, Allen, Yutaka, Naitoh
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Osmoregulatory Capacity of Contractile Vacuoles
Nature, 1948THE view that the contractile vacuoles of Protozoa in many cases perform an osmoregulatory function has been supported by much evidence1 which need not be repeated here. Recent observations carried out on the freshwater peritrich ciliate Carchesium aselli have demonstrated the remarkably close regulation of body volume which is achieved in spite of ...
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Nature, 1921
IN connection with previous correspondence on the mode of production of the contractile vacuole in Protozoa (NATURE, vol. cvi., pp. 343, 376, 441), I find that it is, in point of fact, Prof. Marcus Hartog to whom the credit of the osmotic view is to be given. In a communication to the British Association in 1888 (Rep., p. 714) this observer pointed out
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IN connection with previous correspondence on the mode of production of the contractile vacuole in Protozoa (NATURE, vol. cvi., pp. 343, 376, 441), I find that it is, in point of fact, Prof. Marcus Hartog to whom the credit of the osmotic view is to be given. In a communication to the British Association in 1888 (Rep., p. 714) this observer pointed out
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Contractile Vacuole Complexes in Algae
1984Contractile vacuoles are organelles which occur in many protists and some freshwater sponges. They are defined by their behaviour of slowly filling with fluid and periodically expelling this fluid from the cell (for review see Patterson 1980). Contractile vacuoles form one part of a more extensive organelle, the contractile vacuole complex.
K. Hausmann, D. J. Patterson
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The contractile vacuole and its membrane dynamics
BioEssays, 2000The contractile vacuole (CV) is an osmoregulatory organelle whose mechanisms of function are poorly understood. Immunological studies in the last decade have demonstrated abundant proton-translocating V-type ATPases (V-ATPases) in its membrane that could provide the energy, from proton electrochemical gradients, for moving ions into the CV to be ...
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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
M, Ahmad, P, Couillard
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Contractile Vacuoles of Protozoa
1956A contractile vacuole is a vesicle containing water and lying within the cytoplasm of the cell. It increases in volume, and finally discharges its contents to the outside. In many Protozoa there is a permanent position at which contractile vacuoles continually form, grow and discharge.
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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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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 ...
B, Schmidt-Nielsen, C R, Schrauger
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Structure and behavior of contractile vacuoles inChlamydomonas reinhardtii
Protoplasma, 1997The contractile vacuole (CV) cycle ofChlamydomonas reinhardtii has been investigated by videomicroscopy and electron microscopy. Correlation of the two kinds of observation indicates that the total cycle (15 s under the hypo-osmotic conditions used for videomicroscopy) can be divided into early, middle, and late stages.
Peter Luykx +2 more
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