The red color is the result of iron oxide or rust.

VOA: special.2009.04.15

And in red is a hair cell marker that labels sensory hair cells and the yellow color is the composite color of the green and the red.

红色部分是遗传标记,代表的是听觉毛细胞,黄色是,红和绿两色的复合色。

斯坦福公开课 - 7个颠覆你思想的演讲课程节选

As I say, red tends to be chosen, but then if you get lab experiments showing that that particular color of gas blue is somehow or another sort of more invasive of your consciousness than red is, then you move away from the arbitrariness of the choice of red as a color.

所以人们就倾向于选择红灯，但是如果你想用实验证明,比如说烟蓝色或者,其他任何另一种颜色比红色更加醒目，那么你就忽视了颜色选择上的任意性。

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