評論
打印
A listener from Ontario, California wrote to A Moment of Science with a question her sons hadasked her.
一位來自加利福尼亞安大略的聽眾我們給寫信詢問她兒子們遇到的問題。
The boys wondered why is it that when you get sunburned you often feel chilled.
這些小男孩想知道為什么人曬傷的時候會覺得冷。
It really doesseem like a contradiction: you've been burned, but you feel cold.
這簡直就是矛盾至極:你明明曬傷了，卻覺得冷。
The answer to this seeming contradiction is in your blood.
這個看上去自相矛盾的問題的答案就在你的血液當中。
Sunburn is an injury to your skin, and your body's usual reaction to being injured is to enlarge theblood vessels in the damaged area.
曬傷表明你的皮膚受到了損傷，而通常人體應對損傷的辦法就是使受創的血管擴張。
This allows more blood to be circulated near the injury, whereit can deliver cells to help heal the wound.
這使得更多的血液在傷口附近循環，同時血液中的一些細胞也會被輸送到傷口附近，幫助傷口愈合。
Since sunburn is usually damage to the surface of your skin, the blood vessels in the area of theburned skin enlarge so that more blood is circulated there; this is where the redness comes from.
由于曬傷通常會損害你的皮膚表面，而曬傷部位的血管會擴張，使更多的血液在附近循環。這就是為什么曬傷部位會變紅。
When you're sunburned a large area of your body is usually involved, so a result of so muchblood being near the surface of your skin is that you lose more than a normal amount of bodyheat through it.
曬傷通常會波及到人體的大部分區域。而大量血液聚集在皮膚表面附近的結果就是:你會散失比平時更多的熱量。
Your brain tries to balance this loss of heat by activating reactions which attempt to conserveheat.
為了平衡損失，大腦嘗試通過刺激人體作出某種反應來保存熱量。
A common reaction is shivering, which is the body trying to generate heat in an effort tocompensate for the heat that is being lost.
該反應通常表現為顫抖，這一動作表明人體正試圖產生熱量來補充正在散失的那一部分。
So, even when your skin feels hot to the touch, you shiver and feel chilled as your body tries tomake up for the extra heat loss.
因此，即使你的皮膚摸一下都覺得發燙，但你還是會顫抖，覺得冷，因為這是人體正設法補充額外散失的熱量。
