首页
登录
职称英语
The most popular organic gem is the pearl. A pearl is the response of a mari
The most popular organic gem is the pearl. A pearl is the response of a mari
游客
2025-02-03
10
管理
问题
The most popular organic gem is the pearl. A pearl is the response of a marine mollusk to the presence of an irritating impurity accidentally introduced into its body; a cultured pearl is the result of the intentional insertion of a mother-of-pearl bead into a live mollusk. Whether introduced accidentally or intentionally, the pearl-making process is the same: the mollusk coats the irritant with a substance called nacre. Nacre is composed chiefly of calcium carbonate. Because very few natural pearls are now on the market, most pearls used in fine jewelry are cultured. These include "Biwa" pearls and most other freshwater pearls. Cultured pearls are not easily distinguished from natural pearls except by an expert. [br] Cultured pearl is formed by ______.
选项
A、insertion of a pearl into a live mollusk
B、an oyster into which a piece of grit has been placed
C、putting in a live mollusk
D、placing a bead into culture
答案
B
解析
文章第二句(…a cultured pearl is the result of the intentional insertion of a mother- of-pearl bead into a live mollusk.)指出:人工培育的珍珠是在活的贝类中人为加入珍珠母珠(the intentional insertion of a mother-of-pearl bead):所以选项 B.an oyster into which a piece of grit(粗沙)has been placed正确。
转载请注明原文地址:https://tihaiku.com/zcyy/3940803.html
相关试题推荐
Themostpopularorganicgemisthepearl.Apearlistheresponseofamari
Themostpopularorganicgemisthepearl.Apearlistheresponseofamari
Themostpopularorganicgemisthepearl.Apearlistheresponseofamari
Electronicmailhasbecomeanextremelyimportantandpopularmeansofcommu
Electronicmailhasbecomeanextremelyimportantandpopularmeansofcommu
Electronicmailhasbecomeanextremelyimportantandpopularmeansofcommu
Electronicmailhasbecomeanextremelyimportantandpopularmeansofcommu
Electronicmailhasbecomeanextremelyimportantandpopularmeansofcommu
Electronicmailhasbecomeanextremelyimportantandpopularmeansofcommu
Electronicmailhasbecomeanextremelyimportantandpopularmeansofcommu
随机试题
A.exploreB.distinctC.artisticD.inaccessibleE.subjectiveF.high
Itcanbetemptingtomakeahastydecisionwhenakilleropportunitycomes
[originaltext]M:IneedaDVD-player,butIdon’tknowwheretobuytheminthi
在年度核验中被暂缓登记的图书出版单位,如( )内经整改仍达不到核验要求的,将被
甲公司是一家化工生产企业,生产单一产品,按正常标准成本进行成本控制。公司预计下一
体的质量相同,并且无剩余。最少要装多少瓶?()A.42 B.60 C
下列对原文所阐释整理的概括不正确的一项是: A人是植根于自然的 B其他单
解决城市低收入家庭住房困难的主要途径是()。A.限价商品房 B.公共租赁房屋
完带汤的功用是A.益气健脾,渗湿止泻 B.补脾疏肝,化湿止带 C.益气升阳,
下列关于同一控制下企业合并形成的长期股权投资会计处理表述中,正确的有()。
最新回复
(
0
)