(n.) An opening in the membranes surrounding the ovum, by which nutrition is assisted and the entrance of the spermatozoa permitted.
(n.) An opening in the outer coat of a seed, through which the fecundating pollen enters the ovule.
Example Sentences:
(1) The micropyle canal measures 8 microns at the opening and tapers to 3.6 microns as it penetrates the membrane.
(2) This stain permits pollen tubes to be traced even up to their entry into the micropyle.
(3) The outer layer formed densely accumulated protrusions, whilst the inner layer was smooth and formed a collar structure around the micropyle.
(4) A micropyle and oocyst residuum are absent, but a polar granule is present.
(5) Only unsporulated oocysts were detected in the intestine, and sporulation occurred when feces containing oocysts were incubated for 48 h in seawater at 21 degrees C. Oocysts are elongated (24.8 x 14.7 micron) with a wall about 200 nm thick and have no residuum, micropyle, or polar granule.
(6) Contrary to the widely accepted view that chiton sperm lack acrosomes and that fertilization in this group occurs via a micropyle, we demonstrate here that fertilization in Tonicella lineata occurs by acrosome-mediated sperm-egg fusion.
(7) Sperm from the white sturgeon, Acipenser transmontanus possess an acrosome while the eggs possess numerous micropyles.
(8) were ovoid, 17.6 X 13.6 (16-20 X 11-16) micron; micropyle and oocyst residuum were absent, but a polar body was present.
(9) The plastron region partially encircles the micropyle (anterior end) of the egg and extends along the dorsal surface to the posterior pole; it is delineated laterally by the hatch lines.
(10) Sperm stored in the spermatheca probably is pumped onto the micropyle of the egg during this pause.
(11) are ellipsoidal, 27.3 x 23.6 (22-30 x 20-27) microns; a polar body is present, but no oocyst residuum or micropyle occurs.
(12) The structure of oocysts is described; a peculiar bumpy surface and a calyx-like thickening around the micropyle are illustrated by scanning electron microscopy.
(13) The oocyst wall is smooth, single-layered, with no micropyle.
(14) This indicates a new function for these cells though previously to contribute mainly in the formation of the micropyle.
(15) Neither micropyle, polar granules, nor oocyst residuum were present.
(16) A rapid and steady growth of pollen tubes, their accumulation near the micropyle and penetration in it are observed in self-fertile plants.
(17) After microinjection into fertilized, nonactivated Atlantic salmon eggs via the micropyle, transgenic Atlantic salmon were generated.
(18) are spheroid or subspheroid, 24.6 x 23.5 (21-27 x 20-25) microns, with a shape index of 1.05 (1.0-1.09) but with no micropyle, oocyst residuum, or polar granules.
(19) A micropyle and micropylar cap were observed, but a polar granule and oocyst residuum were absent.
(20) The oocyst wall is a single, colorless layer about 0.6-1.0 microns thick with no striations or micropyle.
Ovum
Definition:
(n.) A more or less spherical and transparent mass of granular protoplasm, which by a process of multiplication and growth develops into a mass of cells, constituting a new individual like the parent; an egg, spore, germ, or germ cell. See Illust. of Mycropyle.
(n.) One of the series of egg-shaped ornaments into which the ovolo is often carved.
Example Sentences:
(1) A specimen of a very early ovum, 4 to 6 days old, shown in the luminal form of imbedding before any hemorrhage has taken place, confirms that the luminal form of imbedding does occur.
(2) The results indicate that the sperm swelling test and the zona-free hamster ovum penetration assay are evaluating different functional qualities of sperm that are apparently not associated with each other.
(3) This study documents a molecular change in the murine ovum related to its exposure to oviductal fluid.
(4) The OCI-related membrane appeared a cause of OCI interference with fimbrial ovum capture by preventing the contact between the fimbrial cilia and the cumulus oophorus.
(5) Also, for determination of the fertilizing capacity of the semen, a zona-free hamster ovum penetration test was done in 49 men, while 14 men were studied by determination of the fertilization of human oocytes in vitro.
(6) The antiprogesterone RU 486 was utilized to evaluate the possible role of progesterone in ovum maturation, ovulation, fertilization, and embryo cleavage.
(7) It is suggested that the beta inhibitory activity of the uterus and the alpha excitatory activity of the rest of the oviduct are involved in the regulation of ovum transport.
(8) Among antigens possible unique to the reproductive process, sperm antigens, antigens of seminal plasma and of the ovum, antigens of placental hormones and of placenta specific proteins appear suitable targets of the production of fertility regulating vaccines.
(9) The preovulatory surge of gonadotropins activates a cascade of proteolytic enzymes resulting in the rupture of the follicular wall and the release of a fertilizable ovum during ovulation.
(10) The development of vaginal ultrasound transducers has facilitated ovum pick-up (OPU) by providing higher precision and less trauma than are found with laparoscopy and other ultrasound-assisted techniques.
(11) In Johnson v. Calvert, a surrogate mother in California failed to gain custody of the child she bore after gestating an embryo from the ovum and sperm of the couple who hired her.
(12) Risk factors that may theoretically alter ovum quality or the hormonal environment include ovulation induction, fertilization in vitro, delayed ovulation, and transperitoneal ovum migration.
(13) Thus, spermatozoa deposited in the vicinity of the USHG immediately following oviposition (to simulate a release of spermatozoa from this region) can be transported to the infundibulum and effectively fertilize the next ovum ovulated.
(14) However, they do not as yet permit a judgment as to the degree that ovum pickup through a fistula was impaired.
(15) We evaluated the differences between this group and those patients presenting either with a blighted ovum or beyond the first trimester, as well as the outcome of those patients with spotting early in gestation.
(16) It is too soon to learn whether this method will be reversible, but use of silastic should prevent adhesions while providing another mechanical barrier between ovum and sperm.
(17) Indomethacin was effective in preventing follicular rupture and ovum extrusion when administered simultaneously with gonadotropin.
(18) A 33% clinical pregnancy rate per ovum pick-up was achieved with the Buserelin-hMG treatment.
(19) The pregnancy rates were higher than a matched IVF series in the male factor and female ASAB groups and reached statistical significance for the ovum donation group.
(20) Lamellar structures, therefore, are considered to be storage material chiefly used in the second half of the cleavage for developmental processes in the rat ovum.