Search results
Results From The WOW.Com Content Network
Tripneustes depressus is the largest sea urchin species in the Galápagos Islands with a mean diameter of 11.5 cm (4.5 in). The growth rate averages 0.5 mm (0.02 in) per month. [ 4 ] There is very little difference in morphology between T. depressus , Tripneustes gratilla and Tripneustes ventricosus ; they are suspected of being the same ...
Tripneustes ventricosus, commonly called the West Indian sea egg or white sea urchin, is a species of sea urchin. It is common in the Caribbean Sea , the Bahamas and Florida and may be found at depths of less than 10 metres (33 ft).
Tripneustes gratilla, the collector urchin, is a species of sea urchin. Collector urchins are found at depths of 2 to 30 metres (7 to 100 ft) in the waters of the Indo-Pacific, Hawaii, the Red Sea, and The Bahamas. They can reach 10 to 15 centimetres (4 to 6 in) in size.
The prevention of polyspermy in sea urchins depends on a change in the electrical charge across the surface of the egg, which is caused by the fusion of the first sperm with the egg. [7] Unfertilized sea urchin eggs have a negative charge inside, but the charge becomes positive upon fertilization.
Egg jelly can vary in composition and complexity from the relatively homogenous single layer sea urchin egg to the three layer egg jelly in starfish. [5] There is an increasing concern in how ocean acidification will affect the fertilization of eggs. In H. tuberculate, low pH can damage the eggs chemical influence on sperm mobility and velocity ...
Toxopneustes pileolus, commonly known as the flower urchin, is a widespread and commonly encountered species of sea urchin from the Indo-West Pacific. It is considered highly dangerous, as it is capable of delivering extremely painful and medically significant stings when touched.
Sea urchin eggs are transparent and can be manipulated easily in the research laboratory. Their eggs can be easily fertilized and then develop rapidly and synchronously. [6] [7] For decades, the sea urchin embryo has been used to establish the chromosome theory of heredity, the description of centrosomes, parthenogenesis, and fertilization.
Strongylocentrotus purpuratus is a species of sea urchin in the family Strongylocentrotidae commonly known as the purple sea urchin. It lives along the eastern edge of the Pacific Ocean extending from Ensenada , Mexico , to British Columbia , Canada . [ 1 ]