字幕列表 影片播放 列印英文字幕 Smart Learning for All How are pearls formed? It's a top secret. I can't reveal it. All right. I will tell you. Pearls are the result of a biological process within living sea creatures. Like an oyster as it protects itself from foreign substances. Wow The oyster looks beautiful. Indeed. An oyster has two shells. Inside the shells, there is an organ called mantle. Mantle covers and protects all the internal organs of the oyster. Whenever any foreign substance like a grain of sand or a parasite makes its way into the oyster. Gets stuck in between the shell and mantle. The mantle's natural reaction is to cover that foreign substance to protect the oyster's internal organs. For this, the mantle secretes a mineral called nacre around the foreign substance in layers. Over time, layer upon layer of nacre leads to the formation of a pearl. For more educational videos please visit http://www.SmartLearningforAll.com Also, don't forget to subscribe to our YouTube channel.
B2 中高級 美國腔 珍珠是如何形成的?#aumsum (How are pearls formed? | #aumsum) 19 1 AumSum 發佈於 2021 年 01 月 14 日 更多分享 分享 收藏 回報 影片單字