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ambience: gorilla vocalizations The creatures of the rain forest are at risk from a whole range of human activities -- from hunting to destruction of their habitat. Scientists say that in central Africa, some wild animals are facing another threat fr
Why Doesnt Honey Spoil? If you havent cleaned out your refrigerator in a while, there might be a nasty surprise waiting for you. There, in a forgotten piece of Tupperware, lurks the ravioli you didnt finish three weeks ago. Opening the lid with curio
Why Did Cleopatra Wear Makeup? Over five thousand years ago, the ancient Egyptians used eye shadow, not only for cosmetic but practical purposes as well. Dark pigment painted around the eye helped protect the eye from the bright midday sun glaring of
Why Does My Body Want To Snack? Sometimes a snack quiets your growling stomach. But sometimes you just feel like munching, even though youre not really hungry. French researchers recently found that this second type of snack attack is harder on your
If blood didnt circulate through our bodies, carrying oxygen and nutrients, we wouldnt be able to live. Blood is so important to life that the body constantly makes new blood. To do this, the body must produce the liquid part of blood, called plasma,
How Does Ice Cool Drinks? Heres something we tend to take for granted: drop a few ice cubes into a glass of water at room temperature, and in a few minutes the water will cool. How does this work? Heat is a measure of molecular activity: the faster a
Fencing in Bacteria 绿脓杆菌(p.aeruginosa)或称铜绿色假单胞菌,是一种致病力较低但抗药性强的杆菌。广泛存在于自然界,是伤口感染较常见的一种细菌。能引起化脓性病变。感染后因脓汁和渗出
Zits Versus Hairy Faces 痤疮是发生在毛囊皮脂腺的慢性皮肤病,发生的因素多种多样,但最直接的因素就是毛孔堵塞。毛孔堵塞以后,毛囊里面的油脂排不出来,越积越多就形成一个个小痘痘,青
Megaphones If you want to call to a friend half a block down a crowded street, you might cup your hands around your mouth to better aim your voice. Have you ever wondered why simple megaphonesamplify your voice so well? Actually, they work for two di
Prune Skin 当在浴缸中浸泡过久后,我们的皮肤表层(表皮)吸收了一定水分,于是我们的肌肤看起来就会像老太太的一样了。手和脚的皮肤比身体其他部分的皮肤略厚,所以它们的变化也更引人
The Front End of the Earth 火流星看上去非常明亮,像条闪闪发光的巨大火龙,发着沙沙的响声,有时还有爆炸声。有的火流星甚至在白天也能看到。火流星的出现是因为它的流星体质量较大(质量大
The Ancestry Of Snakes 古生物学界的一部分学者认为,蛇是由陆地蜥蜴的一个分支进化而来的,在进化的过程中,它们的脚逐渐退化消失了,而身子则变得越来越细长。另一种流行观点则认为蛇的前
The Mystery of Photorespiration 光呼吸作用之谜 光呼吸作用-Photorespiration是所有行光合作用的细胞(该处细胞包括原核生物和真核生物,但并非所有这些细胞都能运行完整的光呼吸)在光照和高氧低二
Out for the Count 麻醉药是指能使整个机体或机体局部暂时、可逆性失去知觉及痛觉的药物。根据其作用范围可分为全身麻醉药及局部麻醉药,全身麻醉药及局部麻醉药根据其作用特点和给药方式
Youve Got a Lot of Space between Your Ears Sure, you think the world is full of solid objects. You think the radio youre listening to is solid. You think the floor youre standing on or the chair youre sitting in is solid. Heck, you probably think tha
The Town That Fought A Volcano, And Won 火山喷发(volcanic eruption)是一种奇特的地质现象,是地壳运动的一种表现形式,也是地球内部热能在地表的一种最强烈的显示。是岩浆等喷出物在短时间内从火
美国一项研究显示-准妈妈在孕期的饮食偏好会直接影响到孩子出生后的口味选择。做这项研究的科学家们在实验中发现,胎宝宝能通过子宫品尝到食物的味道。试想一下,如果,准妈妈在怀孕
Dead Zones in the Ocean 所谓海洋死区是指由于海水富营养化日益严重,导致海水中含氧量减少,鱼类等生物无法生存的区域。科学家介绍,人类过量使用化肥、大量生活垃圾、车辆和工厂排放的废
Pump You Up, Break You Down 科学研究证明,使用兴奋剂会对人的身心健康产生许多直接的危害。使用不同种类和不同剂量的禁用药物,对人体的损害程度也不相同。一般说来,使用兴奋剂的主要危害
Swimming With Germs 到游泳馆游泳消暑逐渐成为市民推崇的运动之一。尽管游泳馆都要求游泳者必须办理健康证,但健康证多流于形式,无法起到防范的作用。目前,市内一些大的游泳馆的水质基本