Sexual kubereka mu dzakakwirira uye dzakaderera mhando kasvisto

Propagation hunhu zvipenyu zvose. Izvi zvinopa kukwanisa bereka kutsivana uye akaramba upenyu. In zvipenyu vane sero pezvakaita nemamiriro, asi maberekero kunobva weboka.

siyana kupatsanura mhando kubereka dzave dzichitaurwa nemasayendisiti siyana. Kazhinji vaiona nezvemarudzi matatu kubereka: vegetative, pabonde uye asexual.

Mukupera nyaya, kukura ane muviri rinoitwa kubva sero rimwe chete haina kusiyaniswa pabonde. For vegetative kubereka dzinoratidzwa kukura zvipuka zvine masero akawanda kubva utachiona, dzimwe nguva zvakaoma kusiyanisa.

Sexual kubereka miti inotanga nokuumbwa kuti utachiona masero (gametes). Pasina kubereka ipfupi kuti kwemapazi gametes vari zygote. Izvi zvinonzi muchangosangana uye transmits majini mashoko kubva vabereki vana.

Gametes vari akaumba mune sikarudzi - gametangia. Maruva Vamiririri, izvo kubudikidza pakusangana inozivikanwa, vane upenyu kunoita hwavo, meiosis.

Sexual kubereka haasi maitiro kuti yebhuruu-uswa algae, mabhakitiriya. Not vakawana nzira kubereka uye zvinoverengeka notumwe.

Mhando dzepabonde kubereka panzvimbo dzapasi mhando kasvisto akasiyana. Somuenzaniso, vamwe mutema algae kubereka kwacho kunogona kuitika pasina paumbwe gametes. Panyaya iyi, miviri fiyuzi-celled muviri.

Kwemapazi gametes, vane flagella, rinonzi isogamy. Sexual kubereka Ndiwo algae zhinji.

Unicellular algae (Chlamydomonas vamwe, somuenzaniso) pamwero, pachavo dzikava nhengo dzakavandika Anoumba gametes. In zvipuka zvine masero akawanda Vamiririri gametangia vamwe regai wakasiyana nevamwe masero kana gametangia akaumbwa morphological kusiyana (somuenzaniso, ektokarpusa).

Nokuti vazhinji isogamous algae mamirire geterotallizm (kuvabereki uye vasiri zvepabonde kupesana). Saka pane Fusion pamusoro gametes physiologically zvakasiyana.

Nokuti vamwe algae dzinoratidzwa kubudikidza conjugation: pane "shamhu" munhu protoplast muchitokisi chimwe.

Kwemapazi gametes nedzimwe hukuru pamusoro flagella, rinonzi heterogamy. Remubatanidzwa bezzhgutikovoy hadzi gamete (oocyte) uye kuva flagella (kazhinji) diki mukono (dzisingaoneki) ndiro oogamy. Sexual kubereka ndizvo zvizhinji tsvuku, mashava, diatoms, mutema algae, uyewo mamwe notumwe yakaderera.

Muchangosangana muna gologamnyh, heterogamic, isogamous uye kupfuura oogamnyh Maruva rinoitwa mumvura. A nhamba zvinomera oogamnyh batanidzo kwacho kunoitika muna oogonia (hadzi gametangia). Vari kushingaira kutamira dzisingaoneki akabudiswa mumvura. Basa sokuti nokuda chemotaxis. Saka spermatsii dzvuku algae (dzvuku algae) vanozoona nemvura chekubuda - tinyerere.

Yepamusoro zvirimwa vari oogamnymi. Zvisinei, muchangosangana kunoitika vane nenzira dzakasiyana. Nokuti dzakakwirira zvirimwa anowanzoramba zvipuka zvine masero akawanda gametangia - archegonium (mukadzi) uye antheridia (makono). Chokunze rukoko masero nhengo dzokubereka nadzo dziri chena. In archegonia ovum akaumba mumwe antheridia spermatozoa vari akaumba kazhinji pamatunhu zvizhinji.

Sexual kubereka ferns uye mosses rinoitwa mumvura. Dzisingaoneki masero dzinobva antheridium uye kutamira archegonium. Uyewo, vakagadzirira isa fotereza archegonium akwezve dzisingaoneki rakapinda secrete madzihwa kubva kumusoro. Vachipinda madzihwa, urume pedyo zai, asi merges nomumwe.