(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.
Sperm
Definition:
(n.) The male fecundating fluid; semen. See Semen.
(n.) Spermaceti.
Example Sentences:
(1) A study revealed that the percentage of active sperm in semen 30 seconds after ejaculation was 10.3% when a nonoxynol 9 latex condom was used as opposed to 55.9% in a nonspermicidal condom.
(2) Here we report that sperm from psr males fertilizes eggs, but that the paternal chromosomes are subsequently condensed into a chromatin mass before the first mitotic division of the egg and do not participate in further divisions.
(3) Sperm specimens were obtained from 13 men participating in our in vitro fertilization program.
(4) Whether hen's egg yolk can be used as a sperm motility stimulant in the treatment of such conditions as asthenospermia and oligospermia is subjected for further study.
(5) Sperm were examined at 4.5 h, 8 to 9 h, and 24 to 25 h of incubation (37 degrees C, 5% CO2, and 95% air).
(6) Since the advance and return of sperm inside the tubes could facilitate the interaction of sperm with secretions participating in its maturation, the persistent infertility after vasectomy could be related to the contractile alteration that follows the excessive tubal distention.
(7) Peaks in the sperm index were preceded by 6 days with peaks in the serum testosterone concentration.
(8) Those without sperm, or with cloudy fluid, will require vasoepididymostomy under general or epidural anesthesia, which takes 4-6 hr.
(9) A sperm whale myoglobin gene containing multiple unique restriction sites has been constructed in pUC 18 by sequential assembly of chemically synthesized oligonucleotide fragments.
(10) Major limitations of the conventional sperm penetration assay are the inability to assess several aspects of sperm function (zona binding and penetration) and the absence of human ovulatory products known to influence fertilization.
(11) Couples applying to in vitro fertilization were admitted into this project when the sperm concentration was greater than 20 million per mL and motility greater than 30 per cent.
(12) To develop a new immunobead binding test (IBT) procedure that will detect sperm antibody in cervical mucus (CM), especially in very small samples of mucus.
(13) This procedure can quickly provide acrosome-reacted bull sperm for use with various in vitro fertilization procedures and for assessment of male fertility.
(14) Males were then sacrificed and organ weights, testicular spermatid counts, and cauda epididymal sperm count and sperm morphology were obtained.
(15) The freezing procedure increased sperm motility in approximately 30% of samples from both animals.
(16) The time of sperm penetration in the mouse eggs, however, was delayed for one-half to one hour when ejaculated sperm were used.
(17) The epididymis appeared distended but without any visible sperms.
(18) Liposomes of PC10 rapidly destroyed sperm motility while PC12 acrosome-reacted sperm remained motile for several h. Liposomes of PC with greater than or equal to 14-carbon fatty acyl chains had no effect on the AR or motility of sperm.
(19) Additionally, the data demonstrate that hamster sperm can remain viable for several hours after becoming immotile, and that many of the immotile sperm are capable of being reactivated.
(20) Heterogeneity in thiol content of sperm within individual samples was also observed.