geoscience.net logo
+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Gonadal maturation independent of photic conditions in laboratory reared sea urchins pseudocentrotus depressus and hemicentrotus pulcherrimus


, : Gonadal maturation independent of photic conditions in laboratory reared sea urchins pseudocentrotus depressus and hemicentrotus pulcherrimus. Zoological Science (Tokyo) 5(5): 979-988

The gametogenesis in two species of the laboratory-reared sea urchins, Pseudocentrotus depressus and Hemicentrotus pulcherrimus, were compared under different artificial photic conditions. Juvenile sea urchins derived from zygotes of the same batch were reared under constant illumination at 20.degree. C until they were transferred to experimental environments, where they were kept for about a year. The experimental environments were: continuous light at constant temperature (20.degree. C) (20 LL); continuous light at ambient temperatures (Amb LL); continuous darkness at ambient temperatures (Amb DD); changing photoperiod in phase with ambient daily photoperiod at 20.degree. C (In-phase); changing photoperiod 6 months out of phase with ambient daily photoperiod at 20.degree. C (Out-of-phase); and ambient light at ambient temperatures (Control). The stages in gametogenesis were determined according to a histological standard. In P. depressus, the gonads in the ambient temperature groups (Amb DD, Control) matured simultaneously; the gonads in the constant temperature groups (20 LL, In-phase, Out-of-phase) also became ripe at the same time, but earlier than those in ambient temperature groups (Amb LL was lost by an accident). In H. pulcherrimus, the gonads in ambient temperature groups (Amb LL, Amb DD, Control) ripened simultaneously; but in the groups kept at 20.degree. C (20 LL, In-phase, Out-of-phase), the gonads remained very immature. These results indicate that in the two species no specific photic conditions are required for gametogenesis to proceed. The results in H. pulcherrimus also suggest the presence of a critical temperature to permit the progression of gametogenesis.

US$29.90


Other references

Weisenhorn, D.M.V.gt; Prieto, E.W.ruaga; Wintergerst, E.S.; Celio, M.R., 1995: Differences in calretinin-expression in organotypic cultures incubated in the presence and absence of serum. Society for Neuroscience Abstracts 21(1-3): 810

Spuhler, J.N., 1954: Some problems in the study of quantitative inheritance in man. American Journal of Human Genetics 6(1): 130-9; Discussion, 146-55

Neubauer, E.; Köhler, S.J.; von der Kammer, F.; Laudon, H.; Hofmann, T., 2014: Effect of pH and stream order on iron and arsenic speciation in boreal catchments. Riverine transport of iron (Fe) and arsenic (As) is affected by their associations with natural organic matter (NOM) and suspended iron (oxy)hydroxides. Speciation has a strong influence on element transport from the headwaters to the ocean becaus...

Park, K.; Powers, S.P.; Bosarge, G.S.; Jung, H-Shin., 2014: Plugging the leak: barrier island restoration following Hurricane Katrina enhances larval retention and improves salinity regime for oysters in Mobile Bay, Alabama. Changes in geomorphology of estuaries are common following major perpetuations such as hurricanes and may have profound impacts on biological systems. Hurricane Katrina in 2005 created a new pass, called Katrina Cut, halving Dauphin Island in Mobi...

Mueller, K.; Srinivasan, M.S.; Trolove, M.; McDowell, R.W., 2010: Identifying and linking source areas of flow and P transport in dairy-grazed headwater catchments, North Island, New Zealand. We examined the applicability of the critical-source area (CSA) concept to the dairy-grazed 192-ha Upper Toenepi catchment and its 8.7-ha Kiwitahi sub-catchment, New Zealand. We evaluated if phosphorus (P) transport from land into stream is domina...

Besson, J.E.; Champier, J.; Chambosse, A.M.; Radisson, J.; Berger, M., 1978: Rapid technic for preparation of thyroid ribonucleic acids without phenol. Thyroid tissue was homogenized in 2 M LiCl. The homogenate was alloued to stand 1 h 30 min at 2 degrees C and then centrifuged. The pellet was suspended in 5% triisopropylnaphthalene sulfonic acid (the sodium salt), 0.05 M Tris--HCl, and 0.1 M NaC...

Petrescu C.; Constantinescu V.G., 1972: The hematocrit gradient a complementary method to explorative puncture in the diagnosis of intra cavitary hemorrhage. Romanian Medical Review 16(3): 42-48

Morris, R.P., 1961: Effect of the mother on goal setting behavior of the asthmatic child. Annals of Allergy 19: 44-54

Chinyangarara, Elizabeth J., 1996: Care and support staff training Stress Volunteers. ELEVENTH INTERNATIONAL CONFERENCE ON AIDS Eleventh International Conference on AIDS, Vol Two One world: One hope : 193

Jerison, HJ., 1981: The nature of intelligence. Cetus, 35: 8-11