• Cleavage (crystal), in mineralogy and materials science, is a process of splitting a single crystal. (primidi.com)
  • Cleavage, in mineralogy, is the tendency of crystalline materials to split along definite crystallographic structural planes. (academic.ru)
  • The tendency for certain varieties of metamorphic and sedimentary rock to split along more or less smooth surfaces is sometimes referred to as rock cleavage. (encyclopedia.com)
  • Cleavage (geology) - This article is about rock cleavage, for cleavage in minerals see Cleavage (crystal) Different ways in which a cleavage can develop in a sedimentary rock. (academic.ru)
  • Bond cleavage , or scission , is the splitting of chemical bonds . (wikipedia.org)
  • In some cases, bond cleavage requires catalysts . (wikipedia.org)
  • In homolytic cleavage, or homolysis , the two electrons in a cleaved covalent bond are divided equally between the products. (wikipedia.org)
  • In heterolytic cleavage, or heterolysis , the bond breaks in such a fashion that the originally- shared pair of electrons remain with one of the fragments. (wikipedia.org)
  • Enzymes which catalyse bond cleavage are known as lyases , unless they operate by hydrolysis or oxidoreduction , in which case they are known as hydrolases and oxidoreductases respectively. (wikipedia.org)
  • This is mediated by the homing endonuclease cleavage of a HEG- allele followed by recombination-repair with a HEG+ allele.The majority of the HEGs are encoded in intervening sequences (IVSs). (avhandlingar.se)
  • The first cleavage results in bisection of the zygote into left and right halves. (wikipedia.org)
  • At the third cleavage the halves are oblique to the polar axis and typically produce an upper quartet of smaller cells that come to be set between the furrows of the lower quartet. (bionity.com)
  • All groups showing spiral cleavage are protostomia, such as annelids and mollusks. (bionity.com)
  • Snails, earthworms and flatworms are remarkably different animals, but they all exhibit a very similar mode of early embryogenesis: spiral cleavage. (biologists.org)
  • However, our knowledge of spiral cleavage is still in its infancy. (biologists.org)
  • Lambert, 2010 ) ( Fig. 1 A). Often mistakenly regarded as the typical cleavage pattern of protostomian lineages, spiral cleavage is instead unique to and probably a synapomorphy (ancestral characteristic) of Spiralia (i.e. (biologists.org)
  • The emergence of prominent invertebrate model systems that are not spiral cleavers (such as the fruit fly Drosophila melanogaster or the nematode Caenorhabditis elegans , both belonging to Ecdysozoa: the moulting animals) meant that the study of spiral cleavage fell behind, and ultimately become one of the most under-investigated, yet widespread, developmental strategies in animals. (biologists.org)
  • Therefore, spiralians are important organisms, not only because their unique spiral cleavage enables them to be used to tackle fundamental questions in developmental biology, but also because their phylogenetic position provides a unique window on the bilaterian ancestry. (biologists.org)
  • Spiralians and spiral cleavage. (biologists.org)
  • A) Representatives of the major clades exhibiting spiral cleavage. (biologists.org)
  • This Spotlight aims to briefly capture the resurgence that the study of spiral cleavage is experiencing in recent years. (biologists.org)
  • Cleavage (breasts), partial exposure of the separation between a woman's breasts. (primidi.com)
  • Radial cleavage is characteristic of the deuterostomes , which include some vertebrates and echinoderms , in which the spindle axes are parallel or at right angles to the polar axis of the oocyte . (wikipedia.org)
  • Based on the abundance of the cleavage products, the site most frequently cut is at residue 687, which lies within the Aβ peptide and thus precludes its formation. (pnas.org)
  • In what is now considered a critical event in the disease pathogenesis, the Aβ peptide is released after cleavage by the γ-secretase either between residues 40 and 41 or between residues 42 and 43. (pnas.org)
  • The precise cleavage site of the γ-secretase, and hence the generation of the shorter or longer Aβ peptide, is widely believed to have important pathologic consequences. (pnas.org)
  • Synthetic peptide (Mouse)corresponding to N-terminus of cleavage site (59/60). (abcam.com)
  • Cleavage (breasts) - A woman s cleavage Cleavage, anatomically known as the intramammary cleft, is the space between a woman s breasts lying over the sternum. (academic.ru)
  • In fact, in the in vitro cleavage reaction ( O tsuka and Y onesaki 2005 ), Dmd inhibits the activity of RNase LS (Y. O tsuka and T. Y onesaki , unpublished results). (genetics.org)
  • The Uracil Cleavage System provides two enzymes, which, when added sequentially to a reaction containing a synthetic DNA fragment containing a deoxy-uracil, generate a single nucleotide gap at the location of the uracil residue. (sigmaaldrich.com)
  • The Uracil Cleavage System enzymes are active in most molecular biology reaction buffers, so there is no need to exchange buffers prior to assembling the cleavage reaction. (sigmaaldrich.com)
  • Cleavage (crystal) - Green fluorite with prominent cleavage. (academic.ru)
  • If cleavage at one of the two γ-secretase sites is mediated by two different enzymes, as some data suggested (see refs. (pnas.org)
  • Cleavage ends with the formation of the blastula . (wikipedia.org)
  • 2. The formation of a set of fractures along closely spaced, parallel surfaces in a rock (the term is usually applied to low-grade metamorphic rocks ) by the alignment of various mineralogical and structural elements during metamorphism and deformation, e.g. in slates , where cleavage is due to a parallel arrangement of minerals. (encyclopedia.com)
  • Rotational cleavage involves a normal first division along the meridional axis, giving rise to two daughter cells. (wikipedia.org)
  • malacins at indiana.edu (George Malacinski) Dear George, Cleavage involves a 'pacemaker' area at the animal pole that somehow sets off the synchronous cleavage waves (refs below). (bio.net)
  • Additional analysis suggests that an interaction of the ribosome with a stop codon might affect the site of cleavage by RNase LS in an mRNA molecule. (genetics.org)
  • During characterization of RNase LS activity after infection of a T4 dmd mutant, we found cleavages in T4 soc mRNA when two successive ochre codons were introduced into the open reading frame ( K ai and Y onesaki 2002 ). (genetics.org)
  • BspMI and NmeAIII require 2 copies of its recognition sequence for cleavage to occur. (neb.com)
  • Cleavage enhancement, methods of making a person's breast cleavage look more substantial than it really is. (primidi.com)
  • cleavage, tendency of many minerals to split along definite smooth planar surfaces determined by their crystal structure. (encyclopedia.com)
  • Intracellular free calcium oscillations in normal and cleavage-blocked embryos and artificially activated eggs of Xenopus laevis. (bio.net)
  • With aging, fatty acids are easily attacked by reactive oxygen species, resulting in alterations in membrane fluidity and deformability that could also alter the precise site of γ-secretase cleavage. (pnas.org)
  • Flagstone, slate, and schist are noted for this property, which arises from the parallel alignment of fine, platy mineral grains, themselves displaying cleavage. (encyclopedia.com)
  • The pattern of cleavage varies among animal groups but is quite standard for all individuals in a given species. (britannica.com)
  • We will highlight to what extent the molecular mechanisms of SKI-1/S1P cleavage of viral GPC differ from processing of SKI-1/S1P's cellular substrates and discuss the implications for virus-host interaction and coevolution. (springer.com)