Name: 別分那麼細！我們以前都是女生！ (We were all female)
Uploaded: 2021-01-22T21:01:30.000Z
Duration: 1 min 50 s

Dear gentlemen, SCIENCE has a confession.

親愛的男士們，本頻道有件事要坦白。

你形成生命時，其實是位女性。

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」。

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。

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。

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。

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。

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。

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。

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。

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」。

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。

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。

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。

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。

但可惜的是你的乳房不會發育。

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