(n.) One of the spores contained in the asci of lichens and fungi. [See Illust. of Ascus.]
Example Sentences:
(1) To isolate single spores from adhesive ascospores and the mycelium, the suspension was sucked through a combination of sintered-glass plates with different pore sizes.
(2) (2) Coincident disomy increased as a function of the mean number of disomic chromosomes per spore in each dyad, but this increase differed functionally from that expected if coincident disomy in the two ascospores were a simple, meiotically independent, concomitant of multiple disomy.
(3) Fungi of the class Pyrenomycetes (Ascomycotina) form a morphological series ranging from those that shoot ascospores (sexual spores) forcibly from the ascus (spore sac) to fungi that ooze ascospores or have no obvious mechanism for ascospore release.
(4) SPR6 is inessential for sporulation; mutants that lack SPR6 activity sporulate normally and produce viable ascospores.
(5) Complementation tests defined two new genetic loci (spo19 and spo20) essential for ascospore formation, in addition to the 18 known spo loci (Bresch et al.
(6) The results obtained demonstrate that the REC46 gene product modulates mitotic chromosomal stability and recombination and is essential for sporulation (meiosis and ascospore formation).
(7) The mutual attraction of conidia to protoperithecia of the opposite mating type was studied genetically in crosses where a mixture of conidia from two different strains, one of which was marked by an ascospore color mutant gene tan spore (ts), was applied to protoperithecia.
(8) Trehalose is located in the cytoplasm, whereas trehalase resides within the protein and carbohydrate matrix of the innermost major cell wall layer of the ascospore.
(9) Strains of Yarrowia lipolytica forming exclusively spherical ascospores were developed through inbreeding.
(10) The production of diploid ascospores in these strains is apparently under polygenic control.
(11) Electrophoretic measurements on Saccharomyces cerevisiae ascospores indicated the presence of a surface protein layer which can be removed by papain, chymotrypsin or 8 m urea.
(12) Electrophoretic analysis of fruiting body extracts from Neurospora reveals a characteristic protein, apparently absent in vegetative structures and ascospores, and which increases markedly in relative concentration after fertilization.
(13) Due to the characteristic shape of the ascus and ascospores, T. burgeffiana is to be considered a synonym of M. pulcherrima.
(14) The segregation pattern of this character obtained by random spore analysis of the ascospores derived from the cross of the two strains strongly suggests that the resistance to tetracycline is under mitochondrial control.
(15) Potassium sorbate, sodium benzoate, sulfur dioxide, and diethylpyrocarbonate (DEPC) were tested for their effectiveness in preventing the outgrowth of Byssochlamys nivea Westling ascospores.
(16) In this case germination of the binucleate ascospore is not preceded by a mitosis.
(17) Transcripts for four of the genes were detected in all three spore types; mRNA for the fifth gene was detected in macroconidia and microconidia but not in ascospores.
(18) Further implications of this study suggest the importance of extensive ascospore analysis when investigating the perfect states of fungi in order to avoid creating unwarranted new species.
(19) The species forming asci from conjugating gametangial cells and having ellipsoidal ascospores are transferred to Dipodascus.
(20) Development of the ascospores of Sporopachydermia lactativora and S. cereana was studied in ultrathin sections.
Zygospore
Definition:
(n.) Same as Zygosperm.
(n.) A spore formed by the union of several zoospores; -- called also zygozoospore.
Example Sentences:
(1) Zygospore development in Blakeslea trispora was studied using light microscopy, scanning electron microscopy, transmission electron microscopy and freeze fracturing technique.
(2) However, normal mating efficiencies and high zygospore viability are observed in clonal culture, indicating the unbiased production of functional opposite mating-types.
(3) The zygospore contained a very high concentration of chitin (about 17%), three times more than the mycelial concentrations.
(4) Some of these non-recombinant individuals may be derived from "parthenospores" (dormant asexual cells resembling zygospores).
(5) In order to study the mechanism responsible for the uniparental transmission of the mitochondrial genome in crosses between Chlamydomonas reinhardtii and C. smithii, we have analyzed the fate of mitochondrial DNA during gametogenesis, zygospore differentiation and sporulation by hybridization experiments.
(6) In strain 137F of Chlamydomonas reinhardi, the zygospores undergo one round of nuclear DNA replication followed by three divisions to produce octospores.
(7) The young diploid zygote differentiates into dormant zygospore competent to complete meiosis, or more rarely (2-10% of cases) it undergoes mitosis to produce a stable diploid progeny.
(8) Using appropriate restriction enzymes, we have been unable to detect methylation of the mitochondrial DNA during gametogenesis or zygospore formation.
(9) Light is required for total elimination of mt+ mitochondrial DNA in the zygospores.
(10) Changes in the relative abundance of cell constituents of Entomophthora virulenta Hall & Dunn were studied during the various differentiation phases leading to the formation of zygospores.
(11) Zygophores interlock upon contact and then undergo six successive morphological changes to become a zygospore.
(12) Some zygospores do form in crosses of carA mutants and wild types.
(13) Zygospores from this strain undergo two rounds of nuclear DNA replication prior to the formation of octospores.
(14) The results obtained with D. discoideum macrocysts differ from those obtained with other cellular slime moulds--Dictyostelium mucoroides, Dictyostelium giganteum and Polysphondylium pallidum--and are reminiscent of the results reported for germinated zygospores of Phycomyces blakesleeanus.
(15) Descriptions and illustrations of both the zygosporic and sporangial states are presented.
(16) Almost all of the heat-tolerant isolates were pathogenic to suckling mice and had smooth or undulate, or smooth plus undulate zygospore walls.
(17) Although zygospore (mature zygote) formation in P. blakeslleeanus occurs in liquid glucoseglutamate medium, morphological observations are made more easily when cultures are grown on 1-mm-thick agar medium.