“embryo sac”造句,怎麼用embryo sac造句
The central portion of an ovule in which the embryo sac develops;the megasporangium.
These abnormalities would cause the abnormal structure of mature embryo sac.
Observation of citrus embryo development showed that in 50 days or so after pollination there was only one zygotic embryo in the embryo sac, and nucellar embryo was not yet invaded.
Synergid cells Two haploid cells located near the egg cell at the micropylar end of the embryo sac in flowering plants.
A minute structure in seed plants, containing the embryo sac and surrounded by the nucellus, that develops into a seed after fertilization.
The concept of an alternation of generations can be extended to the flowering plants in which the embryo sac and pollen represent the much reduced famale and male gametophyte generations respectively.
Those abnormal embryo sacs having abnormal fertility dued to no normal eggs, which caused seed setting rate to drop.
Starch grains present in the embryo sac and placenta are utilized by the embryo.
Pollen tube entered the embryo sac via one synergid and in it released two sperms.
At the mature embryo sac stage, some nucellar cells at the chalazal region differentiated into hypostase.
Megaspore tetrad is linear. the chalazal megaspore develops into an embryo sac of polygonum type. Hypostase and special integument tapetum exist in the ovule.
The embryo sacs observation is one of the main study method for embryology.
Then the uninucleate embryo sac forms 7-celled or 8-nucleate embryo sac of polygonum type following its three times division successively.
Observation by paraffin section showed that Lipeng No.2 embryo sac mother cells were almost entirely degenerated during megasporogenesis.
The mature embryo sac has seven cells.
When the free nuclei of the endosperm were 16 or 32, the nucellar embryo initial (s) originated from the nucellar cells near the micropylar end of the embryo sac.
The development of the embryo sac conformed to the Polygonum type.
-
“靈壽”造句,怎麼用靈壽造句
1、大眼睛瘦臉龐,看到精靈壽命長。2、靈壽有眾多的人文古蹟和自然景觀。3、韓宗文,北宋,原籍靈壽今屬河北。4、鸞鳥自歌,鳳鳥自儛,靈壽實華,草木所聚。5、曾率兵攻取中山,因功被封在靈壽,樂羊死後,葬於靈壽,從此樂氏子孫便世代定居在這裡。6、河北靈壽縣*局被指以假拘留...
-
“水果娃娃”造句,怎麼用水果娃娃造句
1、上面有五個可愛的水果娃娃,有橙子。2、看著那些水果娃娃,讓我捧腹大笑。3、秋天果園的風景特別美麗,可愛的水果娃娃對果農的栽培也是不可或缺的。4、可愛的水果娃娃,個個都綻開了笑臉,望著我們,像是在迎接秋姑娘的到來。...
-
“視訊位元率”造句,怎麼用視訊位元率造句
1、圖6顯示了視訊位元率、幀速、視訊大小和高寬比的視訊設定項。2、對檔案大小的貢獻,按重要*的順序,依次是視訊位元率、音訊取樣頻率、音訊位元率,然後是幀速。3、它能實現視訊位元率的情況下,選擇高在設定。4、若要設定最大的視訊位元率(-maxratebitrate),則會需要...
-
“GH169”造句,怎麼用GH169造句
1、InfluenceofDissolutionandShotPeeningonStructureandPropertyofGH169Superalloy;2、FundamentalStudyontheHotWorkingandHeatTreatmentTechnologyofGH169andGH696Superalloys;3、TheabilityofresistancetolowcyclefatigueofPMFGH95ismuchhigherthanthatofG...
相關文章
- Tom'smotherwasveryangryyesterdaybecauseTom
- —Mr.Zhang,mayIborrowsomemopsfromyourclass?—Sure.Afterha...
- Insomanyways,cyberspace(網路空間)mirrorstherealworld.Somepe...
- Maybeyouhaveeverseenacross.Acrosscanbeapieceofjewelryor...
- Ifyoudonotuseyourarmoryourlegsforsometime,theybecomewea...
- MybrotherRonjoinedtheUSarmyafewyearsago.Mostgirls,espec...
- DearXuyi,Perhapsyourproblemcomesfromshyness.Youmightbea...
- BRADGARRETT’SCOMEDYCLUBCategory:Comedy Bestknownforhisr...
- Ifyoudonotuseyourarmsoryourlegsforsometime,theybecomewe...
- Yesterday,Icameacrossmyformerclassmate,buthisname