placenta
placenta
[pləˈsɛntə]
(pl. placentae -tiː 或 placentas)
[pləˈsɛntə]
(pl. placentae -tiː 或 placentas)
- a flattened circular organ in the uterus of pregnant eutherian mammals, nourishing and maintaining the fetus through the umbilical cord
胎盘 - The placenta consists of vascular tissue in which oxygen and nutrients can pass from the mother's blood into that of the fetus, and waste products can pass in the reverse direction. The placenta is expelled from the uterus at the birth of the fetus, when it is often called the afterbirth. Marsupials and monotremes do not develop placentas
- (Botany)(in flowers) part of the ovary wall to which the ovules are attached
(植)（花的）胎座
- late 17th cent.: from Latin, from Greek plakous, plakount- 'flat cake', based on plax, plak- 'flat plate'
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- encircle vt.包围,围绕
- encirclement n.环绕
- enclasp v.抱紧
- enclave n.飞地（指在本国境内的隶属另一国的一块领土）,被包围的领土
- enclises （本词无重音而与前面有重音的词）连续
- enclisis n.（本词无重音而与前面有重音的词的）连读，与前词连接发音，附读
- enclitic adj.附属的 n.附属字
- enclose vt.（用墙、篱笆等）把…围起来,把…装入信封,附入
- enclosed adj.被附上的,（用墙等）围住的,封闭的,与外界隔绝的 v.（用墙、篱笆等）把…围起来( enclose的过去式和过去分词 ),把…装入信封,附入,（尤指墙、篱笆等 ）围住
- enclosure n.圈占,围绕,圈占地,附件
- enclothe vt.给…穿衣，覆盖
- encloud vt.阴云遮蔽，使天阴
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