Die Entwicklung von Vorderdarm, Macromeren und Enddarm unter dem Einfluss von Nähreiern bei Buccinum, Murex und Nucella (Gastrop. Prosobranchia)

Portmann, Alexandra; Sandmeier, E

doi:10.5962/bhl.part.75639

Cited by 5 publications

(3 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…1986). Its nutritional value is suggested also by its endocytotic uptake in early cleavage stages (Elbers and Bluemink, 1960;Fioroni, 1977) and by the presence of a special transitory albumen digestive sac in the embryonic gut of some species (Portmann, 1955;Portmann and Sandmeier, 1965). In the closely allied pulmonates, protein gains in the growing embryo are positively correlated with protein losses in the capsular fluid (Morrill, 1964).…”

Section: Nutritional Role Of Capsular Albumen and Other Suggested Fun...mentioning

confidence: 99%

Studies on the Structure and Function of the Larval Kidney Complex of Prosobranch Gastropods

Rivest

1992

The Biological Bulletin

View full text Add to dashboard Cite

The larval kidneys of prosobranch gastropods have long been assumed to be involved in handling wastes, but with little supporting evidence. In this study, the larval kidneys of Searlesia dira and Nucella canaliculata were studied with light, electron, and fluorescence microscopy. They consist of three cell types: (1) a large external absorptive cell swollen with heterophagosomes and possessing an endocytotically active external surface; (2) an internal crystal cell with numerous vacuole-bound crystals of a calcium salt and with morphologically complex canaliculi; (3) an internal pore cell characterized by slit-pores that lead to subsurface cisternae, a tubular network, and one or two ciliated ducts that open into the hemocoel. Empirical evidence indicates that the absorptive cell rapidly takes up and stores albumen proteins from the capsular fluid. Absorptive cells were found in 17 of 19 species tested, representing three prosobranch orders, but were not found in 2 opisthobranch or 1 pulmonate species. We hypothesize that the absorptive cells have become specialized for the uptake of capsular albumen prior to the functional differentiation of the gut. However, the nutritional importance of the absorbed albumen proteins and the functions of the crystal and pore cells are presently unknown. No evidence for an excretory function was found for the larval kidney complex; it may be a vestigial protonephridium, the components of which have become disorganized and functionally altered.

show abstract

Section: Nutritional Role Of Capsular Albumen and Other Suggested Fun...mentioning

confidence: 99%

Studies on the Structure and Function of the Larval Kidney Complex of Prosobranch Gastropods

Rivest

1992

The Biological Bulletin

View full text Add to dashboard Cite

show abstract

“…Larvae of many gastropods with mixed or entirely encapsulated development have transitory structures that may represent specializations for consumption of nutritive materials such as albumen or nurse eggs (Portmann. 1955;Portmann and Sandmeier, 1965;Gather and Tompa, 1972;Lyons and Spight, 1973;Rivest. 1983Rivest.…”

Section: Introductionmentioning

confidence: 99%

Intracapsular Feeding by Embryos of the Gastropod Genus Littorina

Moran

1999

The Biological Bulletin

View full text Add to dashboard Cite

Many gastropod species develop within egg capsules within which larvae are provided with extraembryonic nutrients. Species with encapsulated development frequently have transitory embryonic organs, such as "larval kidneys," that may represent specializations for consumption of intracapsular nutrition. Larvae of Littorina species with nonplanktonic, encapsulated development consume intracapsular albumen, but they lack obvious morphological modifications for albumen consumption. To determine the mechanism and location of protein uptake, larvae of seven species of Littorina (L. keenae, L. littorea, L. plena, L. saxatilis, L. scutulata, L. sitkana, L. subrotundata) were exposed to solutions of either fluorescently labeled protein (FITC-bovine serum albumen) or ferritin. Under fluorescence microscopy, larvae of all species with encapsulated, nonplanktonic development displayed strong regional affinity for FITC in the ciliated cells of the velum, whereas hatched larvae of planktotrophic Littorina species did not. Transmission electron microscopy of epithelial cells of nonplanktotrophic veligers exposed to ferritin supported the interpretation that localized affinity for labeled protein indicated endocytotic protein uptake. Planktotrophic Littorina and Littorina with encapsulated, nonplanktonic development were shown to share equivalent velar width/larval length ratios during early embryonic development, whereas a literature search suggested that in other nonplanktotrophic prosobranchs the velum is relatively smaller than in planktotrophs. Retention of a large velum in Littorina that develop entirely within egg capsules may facilitate feeding on intracapsular protein, in the absence of specialized assimilative organs found in other species with encapsulated development.

show abstract

“…Diese wächst als bei allen Gastropoden bald cilienbesetztes Rohr 2 (Abb. 9,17,23,31,41,53 Buccinum undatum Schnitt durch die Region der Enddarmblase eines späten Veligers nach beendeter Nähreieraufnahme (nach Portmann-Sandmeier 1965). Man beachte den cilienbesetzten Abschnitt und das flache dehnbare Epithel der eigentlichen Blase, sowie die zerkleinerten, in der Blase liegenden Dotterplättchen.…”

Section: Enddarmunclassified

Zur Morphologie und Embryogenese des Darmtraktes und der transitorischen Organe bei Prosobranchiern (Mollusca, Gastropoda)

Fioroni¹

1966

Revue Suisse De Zoologie.

View full text Add to dashboard Cite

Cassidaria spec. Schnitte verschiedener Entwicklungszustände der Macromeren bei jüngeren Veligern. a: junge Macromere; b und c : ältere, unter starker Vakuolenbildung degenerierende Macromeren; b : enthält als Ausnahmefall ein sehr grosses Dotterplättchen. Nel: Nucleolus. Abb. 52. Cassidaria spec. Schnittbild (Champy-Fixierung) der mit eingelagerten kleinen Dottergranula versehenen Macromerenregion eines jüngeren Veligers. Abb. 53. Cassidaria spec. Sagittalschnitt auf der Höhe der Mitteldarmdrüse durch den fast schlüpfreifen Embryo. Fioroni, Pio. 1966. "Zur Morphologie und Embryogenese des Darmtraktes und der transitorischen Organe bei Prosobranchiern (Mollusca, Gastropoda)."

show abstract

Die Entwicklung von Vorderdarm, Macromeren und Enddarm unter dem Einfluss von Nähreiern bei Buccinum, Murex und Nucella (Gastrop. Prosobranchia)

Cited by 5 publications

References 1 publication

Studies on the Structure and Function of the Larval Kidney Complex of Prosobranch Gastropods

Studies on the Structure and Function of the Larval Kidney Complex of Prosobranch Gastropods

Intracapsular Feeding by Embryos of the Gastropod Genus Littorina

Zur Morphologie und Embryogenese des Darmtraktes und der transitorischen Organe bei Prosobranchiern (Mollusca, Gastropoda)

Contact Info

Product

Resources

About