(n.) Any one of numerous species of small apterous insects belonging to the order Thysanura. They have two elastic caudal stylets which can be bent under the abdomen and then suddenly extended like a spring, thus enabling them to leap to a considerable distance. See Collembola, and Podura.
Example Sentences:
(1) Results indicate that a 20-ng dose of cefodizime on alternate days may shorten an infradian period (of molt) in the springtail.
(2) A third-generation cephalosporine, cefodizime, was tested in two experiments on the springtail, Folsomia candida, used as a model of infradian rhythmicity.
(3) in snails, from 3 to 0.6 micrograms g-1, in springtails from 5 to 105; in beetles (Amara fusca) from 3 to 1, in spiders from 13 to 11, and in harvestman from 31 to 77 micrograms g-1.
(4) The effect of shifts at different intervals of a regimen of quasioptimal and nonoptimal ambient temperatures alternating at 12-hr intervals was tested on the springtail, Folsomia candida.
(5) Our own studies of Folsomia candida at 23 degrees C show that the incidence of molting in 24 springtails observed at 3-hr intervals for 17 days is characterized by a prominent circadian rhythmicity and an infradian periodicity with a period of about 3 days.
(6) Microflora (bacteria and fungi), microfauna (including nematodes and the protozoa living in the water films around soil pores) and mesofauna (such as mites and springtails), can't possibly be 'transplanted' from one place to another and areas rich in obvious ecological value such as forests are likely to also be high in diversity and complexity at this level.
(7) A reanalysis of data published earlier indicates that the springtail, Folsomia candida, kept in continuous darkness, lengthens its intermolt interval (stadia) with age.
Wingless
Definition:
(a.) Having no wings; not able to ascend or fly.
Example Sentences:
(1) The first, the 28A region, gave three recessive lethals and also contains three known visible mutants, spade (spd), Sternopleural (Sp) and wingless (wg); a complex pattern of genetic interaction in the region incorporates both the new and the previously known mutants.
(2) This derepression is independent of two known activators of en expression: en itself and wingless.
(3) Autoregulation graduates to wingless independence, but is transient, and is superseded by an engrailed-independent mode of maintenance.
(4) report cloning of a Drosophila homolog (Dint-1) of the mouse int-1 gene and show that this gene is identical to wingless+.
(5) We show that this out-of-context activation occurs in cells belonging to the anterior compartments of the three thoracic and the A1 to A8 abdominal segments and that it requires the normal function of the polarity genes wingless (wg) and engrailed (en).
(6) We report here that this choice is mediated by wingless (wg), in a function distinct from its early role maintaining en expression.
(7) The segment polarity genes engrailed and wingless are expressed in neighboring stripes of cells on opposite sides of the Drosophila parasegment boundary.
(8) The question we sought to answer was whether in wingless embryos the proximal wing muscles could form a normal pattern in the absence of the humerus and distal wing skeletal elements.
(9) Fleas are small, reddish-brown, wingless insects with a laterally compressed body and a pronounced third pair of legs adapted to leaping.
(10) The wingless (ws) condition is not, therefore, due to a ZPA deficiency.
(11) These results suggest that wingless regulates accumulation of arm protein by a posttranscriptional mechanism.
(12) According to this view, expression of wingless is normally maintained only in those cells receiving an extrinsic signal, encoded by hedgehog, that antagonizes the repressive activity of patched.
(13) Finally, the supracoracoideus muscle was absent in all but one wingless embryo we examined in the present study.
(14) The segment polarity gene wingless has an essential function in cell-to-cell communication during various stages of Drosophila development.
(15) From the study of mutational mosaics in the wingless locus we conclude that mutations in this gene can be autonomous in mosaics.
(16) The subdivisions of the Drosophila embryo, called parasegments, are defined by the interface between cells expressing the homeoprotein Engrailed and cells expressing the secreted protein Wingless.
(17) The ubiquitous effects of ectopic wingless expression may indicate that most cells in the embryo can receive and interpret the wingless signal.
(18) Finally, the decreased motoneuron number in the wingless LMC, when compared to normal after the cell death period, cannot be totally accounted for by the additional loss of cells that occurred during the cell death period in the wingless LMC.
(19) The phenotype of heatshocked HS-wg embryos resembles the segment polarity mutant naked, suggesting that embryos that overexpress wingless or lack the naked gene enter similar developmental pathways.
(20) Furthermore, the products of engrailed, wingless and hedgehog are essential for maintaining the normal pattern of expression of patched.