Life Cycle of Potamothrix Hammoniensis (Tubificidae) in the Profundal of a Eutrophic Lake

Pétur M. Jónasson; Frode Thorhauge; Petur M. Jonasson

doi:10.2307/3543400

Production of Potamothrix hammoniensis in the Profundal of Eutrophic Lake Esrom

Oikos ◽

10.2307/3543899 ◽

1976 ◽

Vol 27 (2) ◽

pp. 204 ◽

Cited By ~ 25

Author(s):

P. M. Jónasson ◽

F. Thorhauge ◽

P. M. Jonasson

Keyword(s):

Eutrophic Lake ◽

Potamothrix Hammoniensis

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Bionomics of Dytiscus alaskanus J. Balfour-Browne (Coleoptera: Dytiscidae) in a central Alberta lake

Canadian Journal of Zoology ◽

10.1139/z85-198 ◽

1985 ◽

Vol 63 (6) ◽

pp. 1316-1323 ◽

Cited By ~ 17

Author(s):

R. B. Aiken ◽

C. W. Wilkinson

Keyword(s):

Life History ◽

Life Cycle ◽

North America ◽

Population Growth ◽

Population Size ◽

Total Population ◽

Eutrophic Lake ◽

North Central ◽

Total Population Size

There are few studies of life history and population growth of large dytiscid beetles in North America. We sampled populations of Dytiscus alaskanus in a eutrophic lake in north central Alberta weekly in the summers of 1982 and 1983. Like many other temperate zone dytiscids, D. alaskanus has a univoltine life cycle. Dytiscus alaskanus prefers the area at the limit of emergent vegetation in the lake and is most often associated with shoreline vegetation of cattail and sedge. Populations of adult D. alaskanus are at a peak in the late spring and decline throughout the summer. Mark–recapture experiments allowed determination of total population size and monitoring of movement patterns in the lake. Data are discussed with reference to the relatively short summer with which these beetles must cope.

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Effect of Larval Density on Temporal Variation in Life Cycle Patterns of Chironomus plumosus(L.)(Diptera: Chironomidae) in the Profundal Zone of Eutrophic Lake Suwa during 1982-1995.

Japanese Journal of Limnology (Rikusuigaku Zasshi) ◽

10.3739/rikusui.59.13 ◽

1998 ◽

Vol 59 (1) ◽

pp. 13-26 ◽

Cited By ~ 9

Author(s):

Ryoji NAKAZATO ◽

Kimio HIRABAYASHI

Keyword(s):

Life Cycle ◽

Temporal Variation ◽

Larval Density ◽

Eutrophic Lake ◽

Chironomus Plumosus ◽

Lake Suwa ◽

Life Cycle Patterns ◽

Profundal Zone

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Ultrastructural analysis of “Sensory” surface nerve endings and “putative” neurotransmitter sites in Schistosoma mansoni Miracidia

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100156791 ◽

1989 ◽

Vol 47 ◽

pp. 962-963

Author(s):

Betty Ruth Jones ◽

Steve Chi-Tang Pan

Keyword(s):

Nervous System ◽

Life Cycle ◽

Schistosoma Mansoni ◽

Snail Host ◽

Complex Life Cycle ◽

Rational Approach ◽

Effective Control ◽

The Social ◽

Social And Economic Development ◽

Basic Biology

INTRODUCTION: Schistosomiasis has been described as “one of the most devastating diseases of mankind, second only to malaria in its deleterious effects on the social and economic development of populations in many warm areas of the world.” The disease is worldwide and is probably spreading faster and becoming more intense than the overall research efforts designed to provide the basis for countering it. Moreover, there are indications that the development of water resources and the demands for increasing cultivation and food in developing countries may prevent adequate control of the disease and thus the number of infections are increasing.Our knowledge of the basic biology of the parasites causing the disease is far from adequate. Such knowledge is essential if we are to develop a rational approach to the effective control of human schistosomiasis. The miracidium is the first infective stage in the complex life cycle of schistosomes. The future of the entire life cycle depends on the capacity and ability of this organism to locate and enter a suitable snail host for further development, Little is known about the nervous system of the miracidium of Schistosoma mansoni and of other trematodes. Studies indicate that miracidia contain a well developed and complex nervous system that may aid the larvae in locating and entering a susceptible snail host (Wilson, 1970; Brooker, 1972; Chernin, 1974; Pan, 1980; Mehlhorn, 1988; and Jones, 1987-1988).

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A freeze-fracture-etched study of the physarum polycephalum plasma membrane during early formation of the macroplasmodial stage

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100147570 ◽

1993 ◽

Vol 51 ◽

pp. 346-347

Author(s):

Randolph W. Taylor ◽

Henrie Treadwell

Keyword(s):

Plasma Membrane ◽

Life Cycle ◽

Growth Phase ◽

Filter Paper ◽

Physarum Polycephalum ◽

Freeze Fracture ◽

Petri Dish ◽

Wire Screen ◽

Wide Mouth ◽

Sterile Filter

The plasma membrane of the Slime Mold, Physarum polycephalum, process unique morphological distinctions at different stages of the life cycle. Investigations of the plasma membrane of P. polycephalum, particularly, the arrangements of the intramembranous particles has provided useful information concerning possible changes occurring in higher organisms. In this report Freeze-fracture-etched techniques were used to investigate 3 hours post-fusion of the macroplasmodia stage of the P. polycephalum plasma membrane.Microplasmodia of Physarum polycephalum (M3C), axenically maintained, were collected in mid-expotential growth phase by centrifugation. Aliquots of microplasmodia were spread in 3 cm circles with a wide mouth pipette onto sterile filter paper which was supported on a wire screen contained in a petri dish. The cells were starved for 2 hrs at 24°C. After starvation, the cells were feed semidefined medium supplemented with hemin and incubated at 24°C. Three hours after incubation, samples were collected randomly from the petri plates, placed in plancettes and frozen with a propane-nitrogen jet freezer.

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