B - bract 中文

bract n.【植物；植物學】苞，托葉；苞片。-let 小苞片。

bract-scale
Gene population encoding proteins that involve in plant defensive reactions and adversity resistance , such as p1a5 gene encoding a non - specific lipid - transfer protein , p1b4 gene encoding a raucaffricine - o - p - d - glucosidase and p2d4 , encoding a proline - rich protein ; ( 2 ) gene populations with antagonistic effects occurred simultaneously in sprouting bract , e . g . , 如pib4基因編碼的葡萄糖昔酶、 pias基因編碼的植物脂肪轉移蛋白、 pzd4基因編碼的一種富含脯氨酸的蛋白都有參與植物的抗逆、防御或應激反應的功能八2 ）幼嫩苞片中有互為桔抗作用的基因同期表達。
Flowers solitary and terminal , white , 10 - 14 cm in diam . , sessile ; bracts and sepals leathery , orbicular , covered with grayish silky hairs outside ; petals 8 , broadly obovate , 5 - 7 cm long , glabrous , basal 1 . 5 cm connate ; stamens in many whorls , 2 . 5 cm long , distinct , glabrous ; ovary hairy , 5 - locular , styles 2 cm long , apex 5 - lobed 花白色，單生于枝頂，直徑10 - 14厘米，無柄；苞片及萼片圓形，革質，外被灰色絹毛；花瓣8 ，闊倒卵形，長5 - 7厘米，無毛，基部連生約1 . 5厘米；雄蕊多輪，長2 . 5厘米，離生，無毛；子房有毛， 5室，花柱長2厘米，先端5淺裂。
For example ， the spiral arrangement of scale - bract complexes on ovule - bearing pine cones ， where the female reproductive organs of conifers are located ， is important to the production of airflow patterns that spiral over the cone ' s surfaces ， thereby passing airborne pollen from one scale to the next 例如，帶有胚珠的松球的鱗苞綜合體的螺旋狀安排，亦即松柏目植物雌性殖器官的所在位置，對于氣流模式的形成與產生殊為重要，而這些氣流模式在松球的表現盤旋上升，從而把在空氣中飛行的花粉從一個鱗苞傳播至下一個鱗苞。
In the most extreme condition in uni - ovulate cone , the female reproductive unit ( fru ) occupies the position of the terminal bud . an evolutionary trend of reduction is supported in the genus from tri - ovulate to uni - ovulate cone , in which the bract number and seed number are reduced , and the seed size and seed surface sculpture are increasing 總之，麻黃屬雌球花有簡化的趨勢，伴隨著這種趨勢，雌球博士學位論文中國麻黃屬植物的分類? ?兼論麻黃屬的演化花苞片數目減少、種子數目減少、種子體積增大、表面復雜度增加。
Differential screening for the library revealed that , 167 of 237 clones randomly selected from the library are positive and represent genes that were exclusively or intensively expressed in bract , which contain inserts ranging from 100 to 2000 bp in length . moreover , except a few clones were expressed predominantly in bract , absolute majority of subtraclive clones were expressed at low level in all checked organs , i . e . , bract , leaf and root 用地高辛標記的珙桐苞片、葉片和根的cdna做探針，與差減雜交所獲得克隆的pcr產物的雜交結果表明，有少數基因在這些器官中都是大量表達，而大多數在這些器官里的表達量均很少，除苞片外，一般均檢測不到，有部分基因在苞片中優勢表達。
Morphology all ephedra species from china are illustrated with great details on male and female cones . the photographs provide valuable information of characters including peduncle of cone , bract , and micropylar tube etc . for classification and identification of ephedra species from china 2 、形態學提供了中國麻黃屬種類的標本(包括模式標本)照片資料及中國麻黃屬植物的雌球花和雄球花的照片資料，為麻黃屬分類和系統學研究提供了證據。
This species is one of perfect materials to examine the developmental mechanism of plant bract , to explore the developmental relationship between leaf and bract , as well as to study the role and essential function of bract on plant reproductive biology and ecology 該物種是研究植物苞片發育的分子機理及探討苞片與葉片發育的相互關系的理想材料，也是探討苞片在植物生殖生物學及生殖生態學中作用和功能的理想材料。
Pseudobaccatae because the bracts of its female cones are fleshy at maturity . 3 . micromorphology seed , synangium , and branchlet surface sculpture of some ephedra species are studied using sem and described for the first time , and their systematic significance is discussed 類型：種子表面平滑，包括：中麻黃( ephedraintermedia ) 、雙穗麻黃、細子麻黃等；類型：種子表面具疣狀突起，僅發現木賊麻黃( e
Reverse northern hybridization indicated that p1a5 gene was over - expressed in bract compared with that in leaf . this expression pattern was further conformed by rt - pcr . sequence analyses revealed that it is a partial sequence of a lipid transfer protein gene 通過抑制性差減雜交的到克隆pias ，反向northern雜交表明它在玖桐苞片中優勢表達，即在苞片中的表達水平遠遠超過在處于同時期的葉片中的表達水平。
Flower - heads narrowly campanulate , 16 - 19 mm long , ca . 6 mm across , usually 2 - 4 in terminal clusters ; peduncle 2 - 8 mm ; involucral bracts ca . in 7 series , ribbed on abaxial surface , apex spiny 葉互生，卵形，長3 - 5 . 5厘米，寬2 - 4厘米，先端短尖，基部近截形，邊緣具疏齒，兩面被長柔毛，具基出脈3條；葉柄長3 - 5毫米。
In virtue of the technique of suppression subtractive hybridization , we had successfully constructed a subtractive library of d . involucrata sprouting bract by taking homochronous leaf as driver in this study 本研究利用新近發展的抑制性差減雜交技術( ssh )成功構建了珙桐幼嫩苞片和葉片差減文庫。
Sequence analyses for those limited amount of inserts indicated that , ( 1 ) a few particular gene populations are expressed in d . involucrata sprouting bract , e . g . , 分析本試驗獲得的烘桐苞片差異表達的有限幾個部分或全長序列的cdna發現：）處于生長發育初期的苞片中有一些較為獨特的基因表達。
A unique developmental aspect involved in the life cycle of davidia involucrata baill . is the formation of two or three large - sized attractive white bracts surrounding a relatively small - sized capitulum 珙桐生活史中較獨特的發育事件是其較小的頭狀花序下形成的2 3個大型苞片。
At the end of february , the bract attained approximately their full size , and a pair of anatropous ovules were initiated on the adaxial surface at the base of the fertile ovuliferous scale 2月底，苞片體積不再發生變化，珠鱗膨大端的基部的近軸面分化出2個倒生胚珠。
Each individual floret of the spikelet is also subtended by two bracts , the lower being called the lemma and the upper the palea 每一朵能發育的花的外面又有兩片鱗片狀的薄片包住，稱為稃片，外面的一片稱外稃，是花基部的苞片，里面的一片稱內稃。
In the early december , the first bract primordium was formed in the axil scale at the cone base , then bract initiation had occurred in acropetal direction 12月初，最初的苞片原基在雌球果原基的鱗片的葉腋處產生，之后其由基部向頂部連續發生。
Description : evergreen trees to 20 m tall , glabrous throughout ; buds , young twigs , lower surfaces of leaves , and bracts covered with white powder 形態特徵:常綠喬木，高達20米；各部均無毛；芽、幼枝、葉背和苞片均背白粉。
Spadix rachis flat , margin with bract - like appendages ; flowers small , monoecious , in 2 series on rachis , apetalous 肉穗花序軸扁平，邊緣有苞片狀附屬物；花小，單性，雌雄同株，呈2列排列于花序軸上，無花被。
Bract scale the structure found in large numbers in the female cone of gymnosperms , each bearing an ovuliferous scale in its axil 苞鱗：在裸子植物的雌球果中大量存在的結構，每個苞鱗都包含一個珠鱗。

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bract

bract n.【植物；植物學】苞，托葉；苞片。-let 小苞片。

bract-scale

At the end of february , the bract attained approximately their full size , and a pair of anatropous ovules were initiated on the adaxial surface at the base of the fertile ovuliferous scale 2月底，苞片體積不再發生變化，珠鱗膨大端的基部的近軸面分化出2個倒生胚珠。

Each individual floret of the spikelet is also subtended by two bracts , the lower being called the lemma and the upper the palea 每一朵能發育的花的外面又有兩片鱗片狀的薄片包住，稱為稃片，外面的一片稱外稃，是花基部的苞片，里面的一片稱內稃。

In the early december , the first bract primordium was formed in the axil scale at the cone base , then bract initiation had occurred in acropetal direction 12月初，最初的苞片原基在雌球果原基的鱗片的葉腋處產生，之后其由基部向頂部連續發生。

Description : evergreen trees to 20 m tall , glabrous throughout ; buds , young twigs , lower surfaces of leaves , and bracts covered with white powder 形態特徵:常綠喬木，高達20米；各部均無毛；芽、幼枝、葉背和苞片均背白粉。

Spadix rachis flat , margin with bract - like appendages ; flowers small , monoecious , in 2 series on rachis , apetalous 肉穗花序軸扁平，邊緣有苞片狀附屬物；花小，單性，雌雄同株，呈2列排列于花序軸上，無花被。

Bract scale the structure found in large numbers in the female cone of gymnosperms , each bearing an ovuliferous scale in its axil 苞鱗：在裸子植物的雌球果中大量存在的結構，每個苞鱗都包含一個珠鱗。