(n.) One of the exceedingly minute spores found in certain flowerless plants, as Selaginella and Isoetes, which bear two kinds of spores, one very much smaller than the other. Cf. Macrospore.
Example Sentences:
(1) Finally, the potential of using microinjection for transforming embryogenic microspores has been evaluated.
(2) A study has been made of the systematic fluctuations in the frequency of microspores in these compartments, when plants are grown under rigidly controlled conditions.
(3) Normal stamens exhibited the synthesis of many polypeptides not found in the mutant, from microspore mother cell to the preanthesis stages.
(4) The microspores were purified by centrifugation and washing and cultured in liquid medium on a membrane support.
(5) Rice (Oryza sativa L., 2n=24) anthers containing microspores in the early-uninucleate to first-mitosis stages were induced successfully to develop into plants in vitro through an intermediary step of callus formation.
(6) With both constructs, the appearance of GUS activity in developing anthers was correlated with the onset of microspore mitosis and increased progressively until anthesis (pollen shed).
(7) It is evident that not only do microspores mature at different rates, but that the maturation rate of individual microspores varies during the developmental sequence.
(8) Hoechst 33342, a nuclear stain, alone or in combination with either or both of the other stains, could be used to highlight the nuclear developmental stage of the microspores.
(9) This family is composed of 10 to 15 closely related genes which are expressed in early stages of microspore development.
(10) Blepharoplast formation and function has been investigated by light and electron microscopy in developing microspores of the water fern Marsilea vestita.
(11) Embryogenic microspores continued to increase in size throughout the culture period and fluoresced when stained with fluoresecein diacetate (FDA).
(12) During normal meiosis the distribution of microtubules follows a specific temporal and spatial pattern that reflects the polar nature of microspore formation.
(13) High expression of the transcript is limited to microspores entering and undergoing mitosis.
(14) Farmer's lung, caused by the inhalation of microspores--particularly of the genus, Thermoactinomyces--has been recognised for the past 30-40 years as a condition affecting adult farm workers, especially up to the mid-sixties when undried crops were still threshed indoors.
(15) Above all, the microspore-derived embryo system is recommended to both plant breeders and plant biochemists for the selection and multiplication of plants of superior quality.
(16) A new allele of the maize A1 gene, a gene required for anthocyanin pigment biosynthesis, was identified in a genetic stock exhibiting a high frequency of chromosome breakage at the second microspore mitosis.
(17) The microspores of Marsilea and Pilularia have non-specific esterase activity concentrated in the intine inthe immediate vicinity of the germinal site; that is, above the position of the future male gametangia.
(18) Two anther cDNA libraries were constructed, one from anthers of 1.2-1.8 mm long buds (sporogenesis library) and one from anthers of 1.8-4.0 mm long buds (microspore development library).
(19) The ultrastructure of the mature spermatozoid of Marsilea vestita was studied after its release from the microspore and prior to its penetration of the egg.
(20) With the microblending technique a mean of 9.4 green plants and 0.4 albino plants were regenerated per plated anther while a mean of only 2.8 green and 0.17 albino plants per anther were regenerated from microspores isolated after pestle maceration of the anthers.
Spore
Definition:
(n.) One of the minute grains in flowerless plants, which are analogous to seeds, as serving to reproduce the species.
(n.) An embryo sac or embryonal vesicle in the ovules of flowering plants.
(n.) A minute grain or germ; a small, round or ovoid body, formed in certain organisms, and by germination giving rise to a new organism; as, the reproductive spores of bacteria, etc.
(n.) One of the parts formed by fission in certain Protozoa. See Spore formation, belw.
Example Sentences:
(1) After absorption of labeled glucose, two pools of trehalose are found in dormant spores, one of which is extractable without breaking the spores, and the other, only after the spores are disintegrated.
(2) The dose response initially resembled that described by Scholer (1959) in which one million spores killed the majority of mice.
(3) Abnormal synaptonemal complexes were seen in all 19 crosses of N. crassa and N. intermedia that were examined, including matings between standard laboratory strains, inversions, Spore killers, and strains collected from nature.
(4) The mutant spores are pleomorphic and differ both in shape and size from the wild-type spores.
(5) The results presented here substantiate the hypothesis that in S. cerevisiae trehalose supplies energy during dormancy of the spores and not during the germination process.
(6) The fungicidal activity of six rabbit neutrophil cationic peptides (NP) against resting (dormant) spores, preincubated (swollen) spores, and hyphae of Aspergillus fumigatus and Rhizopus oryzae was examined.
(7) In the electron microscope large aggregates of beta glycogen particles were seen in the cytoplasm of sporoplasm cells in mature spores.
(8) The spore germination was synchronized by selection of the spores of the definite size and maintenance at a temperature of 0 degrees.
(9) GAD activity appeared in mutant spores after germination and increased to levels comparable to parent spores after 9 min of germination.
(10) The Ca++-form and H+-form spores of Clostridium botulinum 33A were investigated in vivo with respect to their water sorption and heat-resistance characteristics.
(11) Salt concentrations slightly lower than those providing inhibition tended to extend spore outgrowth time at low temperatures.
(12) The AL spores and the GN spores were morphologically distinct.
(13) Studies demonstrated the fact that there are present within the malignant cell and in the immediate area bacterial spores arising from one of several varieties of plant bacteria.
(14) The stages observed were diplokaryotic cells, sporogonial plasmodia, unikaryotic sporoblasts, and spores.
(15) The rod-shaped organism was motile, did not form spores, and had a gram-negative wall structure.
(16) Numerous factors influenced its activity: method of spore production, inherent spore resistance characteristics, alkalination, storage time and storage temperature.
(17) The inoculum level of infected spores in nutrient broth-yeast extract-glucose medium affected the transducing efficiency of SP-10 in lysates of these cultures.
(18) It can be dissociated from the spores using divalent metal chelators and will reassemble on the spores in the presence of calcium.
(19) Stable messenger ribonucleic acid (mRNA) was shown to be involved in both enterotoxin synthesis and synthesis of other spore coat proteins in Clostridium perfringens.
(20) Effects of alpha- or beta-D-glucose on the respiration of germinated spores (only germinated spores not including swollen spores and elongated spores) of Bacillus subtilis and B. megaterium were studied.