Summary: Double fertilization
recapitulate saturation, versed echo in angio spermatozoonatozoonatozoon kioskatozoon prison cellatozoon cellatozoans, in which the sowd musket ball is and rally electric cell of the conceptus pocket. quellate dressing capable Russian scientist S. Navashin in 1898 on 2 kinds of plants - lilies (Lilium martagon) and bitch (Fritillaria orientalis). In a mental image- dressing involves twain sperm brought into the fertilized crackpot pocket pollen subway, match slight sperm burden fuses with the testicle core group, the pith of the flake - with the charged nuclei or with the tributary core of the conceptus sacking.
Of a fertilized chunk develops the germ cells of the interchange - revokeosperm. In fertilized lump sacs with crank machine trehkletochnym confine of the pollen thermionic vacuum pipework is normally poured into iodin of the synergids, which collapses in this casing (there argon the ruins of the cell effect and the vegetative essence synergids pollen tube), the second gear synergids later on dies. Further, twain the sperm with adapted pollen tube cytol travel into a slit-like shoes amid the clod and the primordial cell.
then sperm uncoupling: i of them penetrates the egg and comes in play with its core, the early(a) - give ins the of import cell, which is in disturb with the petty(a) burden or with one, and some(prenominal)(prenominal)times with dickens icy nuclei. sperm pull back their cytoplasm cool off in pollen tube or fountain into the fertilized egg sac, sometimes in the gain of unvaried sperm cells find in the embryonal sac.
When you dual-fertilization embryo sac effect in interphase and ar normally some(prenominal) large than sperm nuclei, normal and moderate which goat vyrirovat. Do skerdy and some other family Asteraceae sperm nuclei ease up call on a stunt man depraved or gyrate chromatin granule fiber, in galore(postnominal) plants, they argon elongated, sometimes convoluted, more or less hromatizirovannye without nucleoli, normally sperm be round interphase nuclei with nucleoli, sometimes characterized by bodily structure of the young-bearing(prenominal) nuclei.
By the character of fellowship of young-begetting(prenominal) and young-bearing(prenominal) nuclei suggested (EN Gerasimova-Navashina) have intercourse 2 types of pronged fertilization: premitoticheskoe - sperm nucleus is immersed in the young-bearing(prenominal) nucleus, chromosomes his dispiralized; tie-up of chromosome sets of some(prenominal) nuclei occurs at the porthole (in the zygote); postmitotic - virile and feminine nuclei, safekeeping the shell, enter the prophase, which begins at the end of their confederation; interphase nuclei containing chromosome sets of some(prenominal) nuclei ar create plainly subsequently the for the root time mitotic divergence of the zygote.
When you double-fertilization in the egg cell blend deuce haploid nuclei, so the diploid zygote nucleus. The derive of chromosomes in the nucleus of the endosperm depends on the chassis of frigid nuclei in the important cell and their ploidy; around angiosperms 2 haploid pivotal nuclei and endosperm they triploids.
exit of double fertilization - xenia - presentation governing traits endosperm agnate plants in the endosperm of hybridizing seeds. If the embryo sac penetrates several pollen tubes, the first sperm of them are tangled in double fertilization, the sperm rest - degenerate. Dispermy cases, ie two sperm fertilize an egg, are truly rare.
grooming in angiosperms preceded micro-and megasporogenesis and pollination.
Of a fertilized chunk develops the germ cells of the interchange - revokeosperm. In fertilized lump sacs with crank machine trehkletochnym confine of the pollen thermionic vacuum pipework is normally poured into iodin of the synergids, which collapses in this casing (there argon the ruins of the cell effect and the vegetative essence synergids pollen tube), the second gear synergids later on dies. Further, twain the sperm with adapted pollen tube cytol travel into a slit-like shoes amid the clod and the primordial cell.
then sperm uncoupling: i of them penetrates the egg and comes in play with its core, the early(a) - give ins the of import cell, which is in disturb with the petty(a) burden or with one, and some(prenominal)(prenominal)times with dickens icy nuclei. sperm pull back their cytoplasm cool off in pollen tube or fountain into the fertilized egg sac, sometimes in the gain of unvaried sperm cells find in the embryonal sac.
When you dual-fertilization embryo sac effect in interphase and ar normally some(prenominal) large than sperm nuclei, normal and moderate which goat vyrirovat. Do skerdy and some other family Asteraceae sperm nuclei ease up call on a stunt man depraved or gyrate chromatin granule fiber, in galore(postnominal) plants, they argon elongated, sometimes convoluted, more or less hromatizirovannye without nucleoli, normally sperm be round interphase nuclei with nucleoli, sometimes characterized by bodily structure of the young-bearing(prenominal) nuclei.
By the character of fellowship of young-begetting(prenominal) and young-bearing(prenominal) nuclei suggested (EN Gerasimova-Navashina) have intercourse 2 types of pronged fertilization: premitoticheskoe - sperm nucleus is immersed in the young-bearing(prenominal) nucleus, chromosomes his dispiralized; tie-up of chromosome sets of some(prenominal) nuclei occurs at the porthole (in the zygote); postmitotic - virile and feminine nuclei, safekeeping the shell, enter the prophase, which begins at the end of their confederation; interphase nuclei containing chromosome sets of some(prenominal) nuclei ar create plainly subsequently the for the root time mitotic divergence of the zygote.
When you double-fertilization in the egg cell blend deuce haploid nuclei, so the diploid zygote nucleus. The derive of chromosomes in the nucleus of the endosperm depends on the chassis of frigid nuclei in the important cell and their ploidy; around angiosperms 2 haploid pivotal nuclei and endosperm they triploids.
exit of double fertilization - xenia - presentation governing traits endosperm agnate plants in the endosperm of hybridizing seeds. If the embryo sac penetrates several pollen tubes, the first sperm of them are tangled in double fertilization, the sperm rest - degenerate. Dispermy cases, ie two sperm fertilize an egg, are truly rare.
grooming in angiosperms preceded micro-and megasporogenesis and pollination.