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Life Sciences Commons

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1989

Selected Works

Physiology

Articles 1 - 3 of 3

Full-Text Articles in Life Sciences

Amino Acid Uptake And Metabolism By Larvae Of The Marine Worm Urechis Caupo (Echiura), A New Species In Axenic Culture, William Jaeckle, Donal T. Manahan May 1989

Amino Acid Uptake And Metabolism By Larvae Of The Marine Worm Urechis Caupo (Echiura), A New Species In Axenic Culture, William Jaeckle, Donal T. Manahan

William Jaeckle

Axenic (bacteria-free) larval cultures of the marine echiuran worm, Urechis caupo, were reliably obtained by aseptically removing gametes directly from the gamete storage organs. Trochophore larvae only removed neutral amino acids from seawater as measured by high-performance liquid chromatography (HPLC). There was no detectable uptake, as measured by HPLC, of acidic or basic amino acids. Kinetic analysis showed that the transport system for alanine in 4-day-old larvae had a Kt of 4-6 μM and a Jmax of 9-10 pmol larva-1 h-1. Following a 50-min exposure, the majority of the radio-activity (95%) from 14C-alanine was found in the trichlo-roacetic acid-soluble fraction. …


Feeding By A “Nonfeeding” Larva: Uptake Of Dissolved Amino Acids From Seawater By Licithotrophic Larvae Of The Gastropod Haliotis Refescens, William Jaeckle Dec 1988

Feeding By A “Nonfeeding” Larva: Uptake Of Dissolved Amino Acids From Seawater By Licithotrophic Larvae Of The Gastropod Haliotis Refescens, William Jaeckle

William Jaeckle

No abstract provided.


Growth And Energy Imbalance During The Development Of A Lecithotrophic Molluscan Larva (Haliotis Rufescens), William Jaeckle, Donal T. Manahan Dec 1988

Growth And Energy Imbalance During The Development Of A Lecithotrophic Molluscan Larva (Haliotis Rufescens), William Jaeckle, Donal T. Manahan

William Jaeckle

Larvae of the gastropod Haliotis rufescens are classified as "nonfeeding" because they cannot capture particular foods. However, for only 1 out of 5 independent cultures was a net decrease observed in dry organic weight during the complete period of larval development (5 to 7 days). In fact, there were net increases in dry organic weight from the oocyte (day 0) to the newly formed veliger larvae (2-day-old). These weight increases during early development could be explained by increases in the amounts of specific biochemical components of the larvae, relative to oocytes. The metabolic rates of larvae were measured (oxygen consumption) …