Studies on a Freezing Storage of Sea Urchins-I
نویسندگان
چکیده
منابع مشابه
Spermine is major polyamine in sea urchins: studies of polyamines and their synthesis in developing sea urchins.
Polyamine synthesis and accumulation was studied in several species of developing sea urchins. Most striking is the presence in the gametes of a large amount of spermine, with low amounts of putrescine and spermidine. This contrasts with the pattern of polyamines present in both micro-organisms and mammals. Micro-organisms contain mainly putrescine and spermidine and adult mammalian tissues usu...
متن کاملREpROdUCTIvE ISOLATION BETwEEN SpECIES OF SEA URChINS
Existing knowledge on reproductive isolating barriers between sea urchin species is reviewed. Experiments involving artificial production of hybrids between congeneric echinoid species have shown that in most cases hybrids are viable and capable of backcrossing. Only species separated for > 5 million yrs show complete post-zygotic isolation. Each potential prezygotic isolating barrier appears t...
متن کاملCan sea urchins beat the heat? Sea urchins, thermal tolerance and climate change
The massive die-off of the long-spined sea urchin, Diadema antillarum, a significant reef grazer, in the mid 1980s was followed by phase shifts from coral dominated to macroalgae dominated reefs in the Caribbean. While Diadema populations have recovered in some reefs with concomitant increases in coral cover, the additional threat of increasing temperatures due to global climate change has not ...
متن کاملEcological role of purple sea urchins.
Sea urchins are major components of marine communities. Their grazing limits algal biomass, and they are preyed upon by many predators. Purple sea urchins (Strongylocentrotus purpuratus) are among the best studied species. They live in environments that alternate between two stable states: luxuriant, species-rich kelp forests and sea urchin-dominated "barrens." The transition from one state to ...
متن کاملGonadal growth and maturation of sea urchins
characterized by intra-gonadal nutrient storage and its use for gametogenesis (Walker et al., 2001). Sea urchin gonads contain two main types of cells: germ cells and nutritive phagocytes, somatic cells common in both sexes that store nutrients necessary for gametogenesis (Walker, 1982). Before the initiation of gametogenesis, the gonads increase in size by accumulating nutrients such as protei...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: NIPPON SUISAN GAKKAISHI
سال: 1970
ISSN: 1349-998X,0021-5392
DOI: 10.2331/suisan.36.617