(n.) A whitish, granular rock, consisting of feldspar and quartz intimately mixed; -- sometimes called whitestone, and leptynite.
Example Sentences:
Metamorphic
Definition:
(a.) Subject to change; changeable; variable.
(a.) Causing a change of structure.
(a.) Pertaining to, produced by, or exhibiting, certain changes which minerals or rocks may have undergone since their original deposition; -- especially applied to the recrystallization which sedimentary rocks have undergone through the influence of heat and pressure, after which they are called metamorphic rocks.
Example Sentences:
(1) Quantitative and morphological data were obtained on developing olfactory axons in the African clawed frog, Xenopus laevis, during late premetamorphosis (stages 48-54), prometamorphosis (stages 55-57), and halfway through metamorphic climax (stages 58-62).
(2) (1) Control tadpoles did not undergo metamorphic change at any of the temperatures tested.
(3) There was a clear asynchrony in innervation, with projections to some terminal zones appearing before projections to others; projections to all terminal zones were present by late metamorphic stages.
(4) The general nerve terminal morphology and pattern of accumulation of acetylcholine receptors at cutaneous pectoris neuromuscular junctions were similar to those of the adult throughout metamorphic climax except that they still contained more than one motor axon.
(5) In contrast, tadpoles allowed to survive up to 6 months showed no loss of motoneurons if they did not enter metamorphic climax.
(6) The association becomes looser at the metamorphic stage and, occasionally, small breaks in the basement membrane are seen.
(7) Large adult animals have statoconia larger than those in early post-metamorphic animals which have just started producing multiple stones.
(8) The possible significance of decline in serum T4 levels to the metamorphic event in lamprey is discussed.
(9) The characteristics of the nuclear T3 receptors present in red blood cells (RBCs) of Rana catesbeiana tadpoles undergoing metamorphic climax have been investigated with a T3 saturation technique.
(10) The inhibition of unusually high endogenous corticosteroid levels in metamorphic larvae with metyrapone restores suppressor function.
(11) The retinotectal connexions of double nasal (NN), double temporal (TT) and double ventral (VV) eyes in juvenile Xenopus were mapped after post-metamorphic removal of the rostral, caudal, medial or lateral tectal halves with the subsequent cutting of the optic nerve of the operated eye.
(12) However, unlike the crossed fibers of the pre-metamorphic dermis, there is no preferred orientation to the fibers in either layer of the post-metamorphic dermis.
(13) Using selected cDNAs, RNA dot blot analysis of liver mRNA from tadpoles at different stages of metamorphosis showed that the level of one thyroid hormone-enhanced mRNA increased during late prometamorphosis and metamorphic climax.
(14) This also permitted the authors to note the absence of any myelofibrosis or metamorphic neo-osteogenesis.
(15) Coal dust of the IV stage of metamorphism was found to have more marked fibrogenic properties.
(16) The post-hatching development can be divided into four phases: planktonic, metamorphic, juvenile, and adult.
(17) They manifested themselves in disorders of the mitotic regimen and intercellular interactions, in atypical proliferations and primary glandular metamorphism of regenerating cells.
(18) Thyroids were taken from subjects representing metamorphic stages I (premetamorphic larvae), II (onset of climax), and VII (completion of gill resorption), as well as from captivity control larvae.
(19) (2) When tadpoles were kept in thyroxine solutions at 5 degrees, there were no changes in developmental morphology, and tadpoles kept at 18 and 20 degrees showed significant metamorphic changes in 5 to 6 days, but there was a high mortality at the higher T4 concentrations.
(20) The result is that four factors metamorphic rock, zinc, copper, chromium are suspected factors.