What's the difference between cotyledon and micropyle?

Cotyledon


Definition:

  • (n.) One of the patches of villi found in some forms of placenta.
  • (n.) A leaf borne by the caulicle or radicle of an embryo; a seed leaf.

Example Sentences:

  • (1) A bovine pregnancy-associated glycoprotein (bPAG) of 67 kDa has previously been isolated from bovine fetal cotyledons.
  • (2) The mRNAs begin to accumulate during late embryogeny, reach maximal levels in seedling cotyledons, are not detected at significant amounts in leaves, and are distributed similarly in cotyledons and axes of seedlings.
  • (3) Dehydrin proteins were some of the most actively synthesised at about the time of maximum fresh weight and represent about 2% of protein in mature cotyledons.
  • (4) The birth weight, placental weight, volume, surface area, and number of cotyledon showed significantly decreasing trends (P less then 0.001) with the fall in socioeconomic group and maternal dietary intakes.
  • (5) Furthermore, catalases from leaves, stems and cotyledons were electrophoretically identical.
  • (6) The preparation and properties of a cell-free protein-synthesizing system from germinating pea cotyledons is described; polyuridylic acid must be added for l-phenylalanine incorporation.
  • (7) Polyadenylated RNA from 2-day-old cotyledons directed synthesis of 56-kDa subunits, whereas 59-kDa subunits predominated after in vitro translation of RNA from 4-day-old cotyledons.
  • (8) Angiotensin caused a 13-fold increase in the umbilical arterial resistance, whereas there were no changes in cotyledon or venous resistances.
  • (9) A histological evaluation of the cotyledons revealed an abnormal placentome structure in the first pregnancy but not in the second.
  • (10) Weights of the fetus, fetal membranes, cotyledons, caruncles, and uterus were recorded as were weights of the fetal liver, heart, kidneys, spleen, lungs, stomach complex, intestines, and semitendinosus muscle.
  • (11) The plants Arabidopsis thaliana grew from cotyledons to flowers during flight.
  • (12) The accumulation of total RNA transcripts of 18 late embryo-abundant (Lea) gene families, each encoding two closely related Lea mRNAs, was measured in cotyledon total RNA during embryogenesis and germination of Gossypium hirsutum L. by RNA dot hybridization.
  • (13) The aim of this work was to investigate the role of phosphoenolpyruvate carboxykinase (ATP:oxaloacetate carboxy-lyase (transphosphorylating) EC 4.1.1.49) in the conversion of fat to sugar by the cotyledons of seedlings of Cucurbita pepo.
  • (14) Tunicamycin inhibited both glycosylation and secretion of PHA by the COS1 cells, a finding indicating an essential role of the oligosaccharides for transport of PHA in these cells in contrast to the situation found in bean cotyledons.
  • (15) Isocitrate lyase (threo-DS-isocitrate glyoxylate-lyase, EC 4.1.3.1) was isolated from cotyledons of Lupinus seedlings, purified 100-fold with respect to its initial specific activity and characterized (Km, pH optimum, Mg2+ requirement, sulfhydryl inhibitors, and synthase activity).
  • (16) In the cells established from cotyledon, the 1-palmitoyl-2-linolenoyl species increased dramatically.
  • (17) The conclusion is drawn that the rate of turnover of phenylalanine ammonia-lyase in dark-grown mustard cotyledons is too rapid compared to the measured rise in enzyme activity for density labelling to reveal directly control over the rate of synthesis de novo by phytochrome.
  • (18) For this purpose we divided the flow length of the cotyledon in central and a peripheral part.
  • (19) Mixing of BAP-treated and untreated cotyledons before polysome isolation showed that the difference in their activity did not result from isolation procedure.
  • (20) Both AS1 and AS2 mRNAs also accumulate to high levels in cotyledons of germinating seedlings and in nitrogen-fixing root nodules.

Micropyle


Definition:

  • (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.