Metamorphosis, biological

Vitamin A [79-80-1] (6) is stmcturaHy similar to vitamin A [68-26-8] and is also found in fish oils. This compound is important biologically for fish and other lower animals. Interestingly, tadpoles require vitamin A but after metamorphosis require vitamin A (8). 

In addition to its role as an intermediate in cholesterol biosynthesis, isopentenyl pyrophosphate is the activated precursor of a huge array of biomolecules with diverse biological roles (Fig. 21-48). They include vitamins A, E, and K plant pigments such as carotene and the phytol chain of chlorophyll natural rubber many essential oils (such as the fragrant principles of lemon oil, eucalyptus, and musk) insect juvenile hormone, which controls metamorphosis dolichols, which serve as lipid-soluble carriers in complex polysaccharide synthesis and ubiquinone and plastoquinone, electron carriers in mitochondria and chloroplasts. Collectively, these molecules are called isoprenoids. More than... 

Calvo, J. and Johnston, I.A. (1992). Influence of rearing temperature on the distribution of muscle fibre types in the turbot, Scophthalmus maximus, at metamorphosis. Journal of Experimental Marine Biology and Ecology 161,45-55. 

Laurence, G.G. (1975). Laboratory growth and metabolism of the winter flounder from hatching through metamorphosis at three temperatures. Marine Biology 32, 223-229. 

Considerable experimental evidence suggests that chemical cues are very important in substrate selection by larvae. In nature, chemical cues may interact with physical or hydrodynamic factors to induce larval settlement.5-7 Despite the evidence that chemical cues are extremely important for settling larvae, the complete chemical identity of the natural inducer molecules is known in very few cases.3-8-11 More commonly, partial chemical characterization has provided clues to the chemical identity of the natural inducers. These partially purified inducers are useful for studying the biology of larval settlement and metamorphosis.912-18... 

Morse, D. E., Recent progress in larval settlement and metamorphosis closing the gaps between molecular biology and ecology, Bull. Mar. Sci., 46, 465, 1990. 

Often biological or biochemical functions are not realized over all the time throughout the lifecycle of some organism but rather operate for limited times and occasions such as reproduction, metamorphosis (role of iodine in amphibia), synthesis of hormons or other signaling components or of anti-eating poisons or repellants or detoxification agents like metallothion-eins. In such cases, the autocatalytic order related to... 

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