Where does all the blood come from in a rare steak?

　　It's not blood. The color of blood comes from hemoglobin; the color of red meat comes from myoglobin, which stores oxygen in the muscles, not the blood.

　　Why does blowing on food cool it?

　　Blowing whisks away newly evaporated molecules to make room for others. Faster evapo-ration means faster cooling.

　　Are green potatoes really poisonous?

　　Yes. The green spots contain solanine(a toxic relative of nicotine), cocaine, and morphine. You're unlikely to O.D, though you'd have to eat your weight in green potato chips to experience any ill effects.

　　Why are there holes in crackers?

　　Makers roll giant spiked rolling pins over sheets of cracker dough to pop air bubbles prior to baking. Failing to do so would cause unsightly burn marks.

　　日常生活中的科学

　　生牛排的血是从哪里来的?

　　那不是血。血的颜色来自于血红素，而红肉(牛,羊肉) 的颜色来自于肌红蛋白,它将氧气而不是血储存至肌肉中。

　　为什么能将食物吹凉?

　　吹气把新蒸发的分子赶走从而给未蒸发的分子腾出了空间。蒸发得越快则凉得越快。

　　绿色的土豆真的有毒吗?

　　是的。绿色的区域含有茄碱(一种有毒的尼古丁类物质),可卡因和吗啡。那虽然不会使你大伤元气,但忍受绿色土豆带来的不良反应你一定会消瘦不少的。

　　为什么薄脆苏打饼干会有洞?

　　饼干制作者用带钉子的巨大擀面杖在做苏打饼干用的干面薄片上滚动,这样其中的气泡在烘前便爆裂了。如果不这样做使会产生难看的烤糊痕迹。

　　(文/王超； 英语辅导报高中教师版 03~04学年度第40期；版权归英语辅导报社所有，独家网络合作伙伴新浪教育，未经许可，不得以任何形式进行转载。)