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Dear gentlemen, SCIENCE has a confession.
親愛的男士們,本頻道有件事要坦白。
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Your life actually began as a female.
你形成生命時,其實是位女性。
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Well, phenotypically or physically speaking that is, though some prefer to call this stage gender neutral.
至少從外觀和身體上來說是這樣,但有些人喜歡稱呼這個時期為「性別中立」。
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As you might know, when two people mate, they each combine half of their genetic information together; 23 chromosomes each.
你或許知道,兩個人性交時會各自將一半的遺傳訊息合併在一起,也就是每人 23 個染色體。
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One pair of these chromosomes helps to determine your sex.
其中一對染色體有助於決定你的性別。
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If you're female, you contain two X chromosomes, one from your mother and one from your father, while males have one X and one Y chromosome.
如果妳是女性,妳有一對X染色體,一個來自於母親,另一個來自於父親,而男性則擁有一個X和一個Y的染色體。
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At the moment of conception, you were of course male or female based on your genes but the Y chromosome doesn't kick in right away.
在受孕的那一刻,基因會決定你是男還是女,但是Y染色體不是一開始就會起作用。
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In fact, the first five to six weeks of embryonic development are attributed to the X chromosome alone, and females grow from embryo to fully developed to the influence of only the X chromosome.
事實上,前 5、6 週胚胎的發育歸因於X染色體,而女性由胚胎到發育完全都只受到X染色體的影響。
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So what does the Y chromosome do?
那麼Y染色體的作用是什麼?
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Once activated, one of the genes on the Y chromosome known as the SRY gene has two functions: to inhibit certain features of the X chromosome and to impose through dominance the physiological traits that a male must have.
在Y染色體中的 SRY 基因一旦被活化,就會有以下兩種功能:抑制X染色體的某些特徵,以及控制並強加影響男性需要具備的生理特性。
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The ovaries descend and become the testes, and the labia fuses to create the scrotum.
卵巢往下降成為睪丸,而陰唇合成為陰囊。
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If you're a male, take a look.
如果你是男性,往下看一看。
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Though it's more pronounced in some men than others, you'll likely notice a line or ridge of tissue on the scrotum, which is called the "scrotal raphe".
雖然有些人會更為明顯,但你可能會注意到陰囊上有一條線或是脊狀的組織,那稱為「陰囊縫」。
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The skin of the scrotum and penis are zipped up like a zipper as the layers of cells develop in the embryo.
當細胞層在胚胎中發育時,陰囊和陰莖的皮膚像拉鍊一樣被拉起來。
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And the male variant of the clitoris?
那麼陰蒂的男性變體呢?
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Yep, that's the penis.
沒錯,就是陰莖。
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If the Y chromosome does not become activated for some reason, then the female phenotype or physical appearance will persist in a male.
如果Y染色體因為某些原因無法活化,那麼女性的顯型或身體外觀就會持續在男性身上。
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Power added, this is also part of the reason males have nipples.
這也是男性也有乳頭的原因之一。
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The nipples form before the activation of the Y chromosome and SRY gene and thus remain through development and life.
在Y染色體和 SRY 基因被啟動前,乳頭就已經形成,並持續存在於往後的發育和人生中。
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But, you don't develop breasts, sorry.
但可惜的是你的乳房不會發育。
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Got a burning question you want answered?
有任何急待解答的疑問嗎?
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Ask it in the comments or on Facebook and Twitter and subscribe for more weekly SCIENCE videos.
在下方留言或在臉書、推特中詢問,記得訂閱看更多每週的科學影片。