Behavior of the lower organisms /

Jennings, H. S.

doi:10.5962/bhl.title.57732

Cited by 80 publications

(74 citation statements)

References 7 publications

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“…Early studies by Mendelssohn (1902a, b, c) and by Jennings (1904Jennings ( , 1906 established that the ciliate protozoon Paramecium avoids regions of extreme temperature and tends to aggregate in a region of intermediate temperature, which for cells grown at 24 "C is 24 to 28 "C. More recent studies (Tawada & Oosawa, 1972;Tawada & Miyamoto, 1973;Nakaoko & Oosawa, 1977) have documented the fact that Paramecium can respond to very small thermal gradients by altering its swimming behaviour, but the means by which such small changes are detected, and the mechanism by which the thermal stimulus is transduced into a behavioural response, remain unknown. Extensive electrophysiological and genetic studies of Paramecium have yielded strong evidence that a variety of chemical and physical stimuli cause depolarization of the surface membrane and the opening of a voltage-sensitive Ca2+ channel.…”

Section: Introductionmentioning

confidence: 99%

Thermosensory Behaviour in Paramecium tetraurelia: a Quantitative Assay and Some Factors that Influence Thermal Avoidance

Hennessey

Nelson

1979

Journal of General Microbiology

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The free-swimming ciliate Paramecium avoids warm regions. We have developed a quantitative assay of thermal avoidance, based on the interference between thermal avoidance and the normal tendency to swim upward (negative geotaxis). Paramecium tetraurelia swimming in a Tris/Ca2+ solution avoided a region warmer than about 40 "C. Several factors influenced the strength of the response, including the concentrations of monovalent cations and Ca2+, the temperature of the test region, and the temperature at which the animals had been cultured. At 1 mM-Ca2+, increasing Na+ concentration enhanced avoidance of a 40 "C region, and at a constant Na+ concentration (0.5 mM), avoidance improved with decreased Ca2+. When the ratio [Na+]/[Ca2+]i was held constant, varying Na+ and Ca2+ concentrations did not affect thermal avoidance. Other monovalent cations (Cs-', Li+, Rb+) and hydroxylamine also enhanced thermal avoidance, and K+ was somewhat less effective than these. The strength of the avoidance response increased with increasing test temperature in the range of 37 to 42 "C for cells grown at 28 "C. Cells grown at 15 "C had a lower threshold for thermal avoidance, and those grown at 35 "C showed no avoidance at 40 "C and only poor avoidance at higher temperatures. Cells cultured at 15 or 35 "C and then shifted to 28 "C acquired the thermal behaviour typical of cells cultured at 28 "C. Behavioural mutants with defective Ca2+ channels (Pawns) are incapable of reversing their swimming direction and showed little or no thermal avoidance. We suggest that thermal avoidance is triggered by thermotropic phase transitions in the lipids of the excitable membrane of Paramecium tetraurelia.

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Section: Introductionmentioning

confidence: 99%

Thermosensory Behaviour in Paramecium tetraurelia: a Quantitative Assay and Some Factors that Influence Thermal Avoidance

Hennessey

Nelson

1979

Journal of General Microbiology

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“…A great variety of organisms and cells trace spiral paths when swimming freely through a medium (3,6,9,10,12). However, little is known about the function of spiral movement in the life of these organisms or of the mechanism determining the spiral path because of difficulty in observation by ordinary light microscope.…”

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confidence: 99%

Relationship between Direction of Rolling and Yawing of Golden Hamster and Sea Urchin Spermatozoa.

Ishijima

Hamaguchi

1992

Cell Struct. Funct.

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ABSTRACT. As a first step towards understanding the function and mechanism of spiral movementof spermatozoa swimming through a medium, the direction of rolling (rotational movementof the spermatozoa around their long axis) and that of yawing (circular motion of spermatozoa upon the surface of a glass microscope slide and coverslip) were examinedfor golden hamster and sea urchin spermatozoa. Most golden hamster spermatozoa yawedclockwise over the upper surface of a glass slide whenviewed from above, whereas in most sea urchin spermatozoa yawing was counterclockwise. Under the lower surface of a coverslip, the direction of yaw of golden hamster or of sea urchin spermatozoa was reversed. Most golden hamster spermatozoarolled counterclockwise as seen from the anterior end, whereas all examinedsea urchin spermatozoa rolled clockwise relative to the observer. On the basis of quantitative analysis of the proportion of spermatozoa rolling (or yawing) clockwise to those rolling (or yawing) counterclockwise, a close relationship between the direction of rolling motion and that of yawing motion was shown for both golden hamster and sea urchin spermatozoa.A great variety of organisms and cells trace spiral paths when swimming freely through a medium (3, 6, 9, 10, 12). However, little is known about the function of spiral movement in the life of these organisms or of the mechanism determining the spiral path because of difficulty in observation by ordinary light microscope.Spermatozoa are particularly suitable for studying these problems because spiral swimming, generated by a single flagellum, can be explained from the combination of two rotations, roll (rotation of the spermatozoa around their longitudinal axis induced by the threedimensional character of bending waves) and yaw (rotation of the spermatozoaaround the axis perpendicular to the beating plane caused by the asymmetry of bending waves) (6). It has long been known that sea urchin spermatozoa yawcounterclockwise over the upper surface of a glass slide or clockwise under the lower surface of a coverslip as viewed from above (1, 4, 5, 16), although some authors have found that a few spermatozoa yaw in a direction contrary to that of the great majority (2, 6). Our recent observations of the rolling motion of various spermatozoa have shown that the direction of rolling motion of the great majority of sea urchin and starfish spermatozoa is opposite to that of medaka, golden hamster, bull or human spermatozoa (8). The esTo whomcorrespondence should be addressed.sential difference in the direction of rolling motion between these two groups implies that the direction of yawing motion of sea urchin and starfish spermatozoa is also opposite to that of other animals. In the present study, the direction of yawing motion of spermatozoa swimmingclose to the surface of a glass slide or of a coverslip and their rolling motion were determined in golden hamster and sea urchin spermatozoa. On the basis of these data, a one-to-one correspondence between the roll direction and the yaw...

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“…Whereas type III excitation may be a defense against injurious stimuli (44) resulting in a direct backing away from them, type II is clearly the physiological mechanism of the "spontaneous" stops and turns in Na+-containing culture media and fresh waters. The change in the rate of this spontaneous avoiding reaction results in the biased random walk tactic behind attraction and repulsion (12,24,44).…”

Section: Discussionmentioning

confidence: 99%

Mutant analysis shows that the Ca2+-induced K+ current shuts off one type of excitation in Paramecium.

Saimi¹,

Hinrichsen²,

Forte³

et al. 1983

Proc. Natl. Acad. Sci. U.S.A.

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Two mutants of Paramecium tetraurelia, called "pantophobiacs," were found to lack most of the slow Ca2+-induced K+ outward current. Passive properties, the transient Ca2' inward current, and the fast depolarization-induced K+ outward current remain normal. The mutant defect reduces the ability to shut off a normal, excited state of the membrane and results in repeated, long backward swimming instead of the wild-type jerks in response to a variety of ions, to heat, and to touch.Certain mutations are known to affect the nervous system and the behavior of animals (1). In Drosophila (2) and Paramecium (3-7), induced mutations can affect the electric properties of the excitable membranes. Because Paramecium is a large cell and therefore suitable for voltage-clamp experiments, several mutations have been shown to alter the currents through different ion channels (8-11). These mutations have been used as blockers to dissect the pathway of electrogenesis and behavior (4-6, 9, 12-15) and to provide the null controls in the measurements of individual ion currents (14-16) or fluxes (17-19). These mutations also have been used as markers in the search for the gene products involved in the ion-channel functions (20)(21)(22).A paramecium is much like a neuron with several kinds of ion channels differing in their properties and locations. It has at least seven kinds of ion channels with different triggering mechanisms, on-kinetics, off-kinetics, and ion selectivities, some of which are located in the somal membrane and others in the ciliary membrane (23,24). The currents through these channels can be separated by standard physiological methods, by the use of mutants (9,(13)(14)(15), and by deciliation (25,26). The Ca2+-induced K+ current is among the seven kinds of membrane currents studied to date. In paramecia, a step depolarization with a voltage clamp induces a transient Ca2+ inward current, followed by a complex K+ outward current. The Ca2+-induced portion of this complex has been estimated by subtracting the outward current of a pawn mutant, which lacks the Ca2+ current and the Ca2+-induced currents, from the outward current of the wild type. The Ca2+-induced K+ current thus isolated activates slowly, reaching its plateau seconds after depolarization (15

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Behavior of the lower organisms /

Abstract: Potassium bromate, Potassium permanganate, Potassium bichromate. Potassium ferricyanide, Ammonium bicliromate.2. Repellent power very weak in proportion to injurious effects ; reaction not completely protective.

Cited by 80 publications

References 7 publications

Thermosensory Behaviour in Paramecium tetraurelia: a Quantitative Assay and Some Factors that Influence Thermal Avoidance

Thermosensory Behaviour in Paramecium tetraurelia: a Quantitative Assay and Some Factors that Influence Thermal Avoidance

Relationship between Direction of Rolling and Yawing of Golden Hamster and Sea Urchin Spermatozoa.

Mutant analysis shows that the Ca2+-induced K+ current shuts off one type of excitation in Paramecium.

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