Njikọta - ihe na-aga na otú? Ugboro abụọ njikọta na okooko

Njikọta - bụ usoro nke-asọkọta ọnụ nke abụọ mkpụrụ ndụ, na-akpata guzobere ọhụrụ mkpụrụ ndụ, na-enye ịrị elu ọzọ organism nke otu genus ma ọ bụ umu. Gịnị bụ a abụọ njikọta na okooko osisi na otú ọ na-adị, na-agụ isiokwu a.

Ihe kachasi mkpa njikọta

Ọ na-abịa dị ka a n'ihi nke anọ na abụọ mkpụrụ ndụ, nwanyi na nwoke, na ntoputa nke a diploid zaigọtụ. Na nke ọ bụla ụzọ chromosomes bụ ugbu otu ọnụmara na otu nne nwa cell. Ihe kachasi mkpa n'ime usoro nke Fertilization bụ iji weghachi diploid set of chromosomes na ikpokọta mkpụrụ ndụ ihe nketa na ihe onwunwe nke nne na nna. Ha na ụmụ ha ga-abụ ihe viable ka ijikọta ndị kasị bara uru àgwà ya na nna ya na nne ya.

Njikọta - ihe ọ bụ?

Nke a usoro nke apostle mmepe nke àkwá na mmakọ nke nuclei. Njikọta - ihe ọ bụ? Nke a bụ ihe irreversible usoro nke pụtara dị ka a n'ihi nke anọ na nke gametes nke dị iche iche sexes na ijikọta ha nuclei. The ịmụpụta egg na-adịghị doro a usoro a ugboro abụọ.

Ma e nwere ndị osisi na-mụta nwa a ọgbọ ọhụrụ naanị nke nne gamete enweghị Fertilization. Nke a amụba a na-akpọ a na-amaghị nwoke. Ọ dị mma ịmara na ndị a ụzọ abụọ nke mmeputakwa na otu ụdị osisi nwere ike interleaved.

Ugboro abụọ njikọta spam nke okooko osisi

Sex mkpụrụ ndụ nke malitere na-akpọ gametes. Na ndị inyom na-akwa, na nwoke - spam na osisi na nkpuru ofu, mgbe spore - mobile. Njikọta - ihe ọ bụ? Ọ bụ onye ahụ nke a akpan akpan cell - na zaigọtụ, nwere butere n'aka àgwà spam na egg.

Okooko osisi nwere mgbagwoju njikọta, nke a na-akpọ a abụọ, n'ihi na mgbakwunye na nke egg na-ịmụpụta site ọzọ pụrụ iche cell. Formation spam na-ewe ebe ájá pollen, na ha maturation a rụrụ na stamens, ma ọ bụ kama na ha anthers. Abù guzobere ovules àkwá-emi odude ke ovary pestle. Mgbe egg na-ịmụpụta spam, ovule site na mmalite ịzụlite osisi.

Iji njikọta na okooko ka mere, mbụ ị mkpa mịa osisi ahụ, ya bụ, na ihere ga-enweta a speck ájá pollen. Ozugbo ihere, ha na-amalite na-eto eto n'ime ovary, dapụtara na a pollen tube. N'out oge, ájá urughuru na-kpụrụ nke abụọ spam mkpụrụ ndụ. Ha adịghị ada ka na-amalite na-akpali kwupụta pollen tube, nke penetrates na ovule. Ebe a, site nkerisi otu cell elongation na guzobere nke ẹmbrayo na nwa.

Ọ dị mkpa n'ihi na ebe nke egg na ya, na ọbụna otu cell, nke na-elekwasị anya a abụọ set nke mkpụrụ ndụ ihe nketa na ozi. Mgbe nke ahụ gasịrị pollen tube Germination pụtara na nwa nwa na anọ na nke spam na egg, na-eduga n'iguzobe na zaigọtụ, na ndị ọzọ na - na a akpan akpan cell. mmepe nke ẹmbrayo si zaigọtụ emee. The abụọ anọ na Nleta nutritive anụ ahụ, endosperm ma ọ bụ na ọ dị mkpa maka oriri na-edozi nke ẹmbrayo na n'oge uto oge.

Ihe dị gị mkpa maka ịdị adị nke ọ bụla ụdị osisi?

• Ihe mbụ i kwesịrị iji weghachi diploid set of chromosomes, na n'ime ya - ha pairing.
• Nye ihe continuity n'etiti ọgbọ, na-esonụ a inwe.
• Ikpokọta na-etolite a otu ụdị ma ọ bụ butere n'aka Njirimara nke ma nne ma nna.

All a mere na mkpụrụ ndụ ihe nketa larịị. Iji ghọtara njikọta, maturation nke nne nwa na nna gametes ga-erukwa n'out oge.

Njikọta na angiosperms

Usoro a na-kọwara nke mbụ a German ọkà mmụta sayensị Strasburger na nkera nke abụọ nke iri na itoolu na narị afọ. Njikọta emee angiosperms mmakọ nke abụọ gametes nuclei dị iche iche: na nwoke na nwaanyị edumbet. Ha cytoplasm na-adịghị etinye aka na njikọta spam. N'ezie njikọta na-adị mgbe ndị spam fuuz na egg ntọala.

The omumu nke spam bụ pollen ọka ma ọ bụ pollen tube. Ọka-amalite na-eto eto mgbe dara na ihere. Time of mmalite nke usoro a, onye ọ bụla osisi dị iche iche, dị ka oge Fertilization. Ka ihe atụ, biiti pollen mkpụrụ asiaha mgbe awa abụọ, na oka - ozugbo. The àmà mbụ nke Germination - ya na-abawanye na olu. Abụkarị otu pollen ọka Nleta otu tube. Ma ụfọdụ osisi na-adịghị isiokwu a na-achị na-etolite multiple handsets, naanị otu onye nke ruru ya mmepe.

Pollen tube na spam na ya ambulant na-etolite ma akpatre etịbede. All na ya bụ n'ime ẹmbrayo nwa. Otu nke infiltrators ebe a spam na ẹkenam n'ime egg na merges na ya haploid ntọala. Njikọta - ihe ọ bụ? Nke a anọ na abụọ nuclei nke spam na egg. The ịmụpụta egg-amalite na-ekewa, nwetara ọhụrụ abụọ mkpụrụ ndụ. Ha na-ekewa n'ime anọ, na na. N'ihi ya, e nwere a multiple nkewa, na nke osisi nwa amalite.

Angiosperm osisi mgbe njikọta nwere ikike ịzụlite a n'ihu ahụ, nke a na-akpọ endosperm. Nke a bụ onye ọzọ karịa ekwukwa n'akwụkwọ nwa Wednesday. Na confluence nke abụọ spam na diploid ntọala a kpụrụ otu onye na-set of chromosomes, abụọ nke - nne nwa si na otu - nna. N'ihi ya, na abụọ njikọta osisi ntule bụ mgbe a spam fuuz na egg, na ndị ọzọ na - na na isi mkpụrụ ndụ, emi odude ke center.

Pụrụ iche na atụmatụ nke angiosperms

• Ọtụtụ mmegharị na-eto eto dị iche iche na ọnọdụ.
• Ugboro abụọ njikọta, nke na-enye ohere ka nwere a ọkọnọ nke bekee mkpa maka nkịtị Germination nke osisi.
• Ọnụnọ nke triploid endosperm.
• Education ovules n'ime ovary, agaghi asu carpel mgbidi na-echebe ha si mebiri.
• Nwa ebu n'afọ na mmepe angiosperms si ovary.
• Ịchọta nkpuru n'ime mkpụrụ osisi ahụ, mgbidi nke na-echebe site na ya.
• Ọnụnọ nke okooko osisi na-eme ka o kwe omume na mịa osisi na ụmụ ahụhụ.

Ekele atụmatụ ndị a angiosperms ogide a kasị ọnọdụ n'ụwa.

Njirimara njikọta spam nke angiosperms

Oputara si eziokwu na ndị a osisi nwere a abụọ njikọta. A pụrụ iche mma na-anọchi anya a onu a na-akpọ Xenu. Ya pụtara dabeere n'eziokwu na pollen-emetụta kpọmkwem Njirimara na e ji mara nke endosperm. Ka ihe atụ, na-ọka.

Ọ bụ a-acha odo odo na-acha ọcha osisi. Ha na agba na-adabere na agba nke endosperm. Mgbe pollination nke nwanyi okooko osisi na pollen Belozernaya oka iche zheltozernogo ya sere ka ga na-acha odo odo, mgbe endosperm development emee on a osisi na-acha ọcha agwa.

Olee ihe bụ ọrụ okooko osisi?

Ndị a osisi na akaụntụ maka 13 000 ịmụ nwa na 250 000 umu. Ha na-n'ọtụtụ ebe gburugburu ụwa. Okooko osisi - a na-na isi mmiri nke Biosphere, mepụta organic bekee kee carbon dioxide na emit oxygen. Na-ata nri nri yinye-amalite na ha. Ọtụtụ ụdị okooko osisi a onye na-eji ihe oriri. N'ime ndị a, na-ewu ụlọ na-eme ka dị iche iche ezinụlọ ihe.

Nwere ike ime na-enweghị ha, na ọgwụ. Ụdị ụfọdụ nke angiosperms bụ isi n'ụwa, ha na-ekere òkè na guzobere na oruru nke ahịhịa cover isi akụkụ nke ala phytomass. Mee elu mee ala, ọ bụ ndị a osisi kpebisiri ike site ekwe omume nke ịdị adị nke mmadụ n'ụwa dị ka a ụdị ndu.