你应该知道的与人体有关的一些数字 1 、肌体每平方英寸含 1.9 亿皮肤细胞 Every square inch of the human body has about 19 million skin cells. 2 、每小时约有 10 亿人体细胞需要更新 Every hour about 1 billion cells in the human bodyhave tobe replaced. 3 、 平均每个人的头发数目为 10 万 The average human head has about 100,000 hairs. 4 、由动脉、静脉和毛细血管组成的循环系统约有 6 万英里 The circulatory system of arteries, veins, and capillaries is about 60,000 miles long. 5 、 平均一个人的一生心跳 25 亿次 The heart beatsover 2.5 billion times in an average lifetime. 6 、 每个人舌头表面、咽喉和上膛部位分布约有 9 千味蕾 There are about 9,000 taste buds on the surface of the tongue, in the throat, and on the roof of the mouth. 7 、 人均每年眨眼次数为 1 千万次 Every personblinks over 10,000,000 times a year. 8 、 人脑均重 3 英镑 The human brain weighsaround 3 pounds. 9 、 一个红血球游遍全身所需时间为 20 秒 It takesroughly 20 seconds for a red blood cell to circle the whole body. 10 、 最强壮的肌肉是舌头 The strongest muscle in the body is the tongue. 11 、心脏能够产生足够的压力，所产生的压强可以把血液喷出肌体 30 英尺 The heart creates enough pressure, whichsquirts theblood by 30 feet. 12 、每个新生儿骨骼大约由 300-350 块骨骼组成，而每个成年人含有 206 块骨骼 A newborn baby’s skeleton consists ofroughly 300~ 350 bones,while a n adult human body consists of 206 bones 13 、每个人含有 600 肌肉 There are 600 muscles in human body 14 、每个人含有 78 个器官，其中 22 为内脏器官 The adult body is made up of 78 organs among which, 22 are internal organs 15 、每个人有 23 对染色体，其中 1 对为性染色体 humans have 46 chromosomes, made up of 23 pairs ， 1pair is for sex determination
转自 http://tech.sina.com.cn/d/2012-07-17/07297395175.shtml 2012年07月17日07:29 新浪科技 地球的伙伴，人类的敌人：研究显示月尘或将对人体产生伤害，这种细微的尘埃曾经长期暴露于紫外射线辐射中，并且棱角锋利 月尘遍布月球表面。即便用上全世界最大功率的吸尘器也没有办法清除全部的月尘 新浪科技讯 北京时间7月17日消息，据英国《每日邮报》报道，当人类向着太空迈出稚嫩的步伐，能定居月球当然是我们长期的目标。但是看起来月球对我们这群到访者可能并没有那么友好，科学家们发现月球上遍布的尘土对于人类探索者们可能是有毒的。 我们都知道月球表面被一层厚厚的原始尘土所覆盖，这些尘土质地极细，因此它们也非常容易被吸入人体，这将导致各种癌症的高发，就和人们在地球上一些地区吸入空气中的悬浮颗粒物和火山尘埃是一样的。 美国田纳西大学的研究人员在谈到美国宇航员尼尔·阿姆斯特朗首次踏上月球表面的壮举时说道：“阿波罗计划的宇航员报告了他们感到皮肤，眼睛和呼吸道的不适感，这可能和他们在月面上的舱外活动有关，月球尘土粘附在他们的宇航服上并随着宇航员被带进了飞船内部。” 到目前为止，人类加起来最多也只在月面上停留2~3天，在这些时间内，宇航员一般是呆在飞船内或者穿着舱外航天服。但是如果要想进行长期驻留，研究人员认为这样的月尘吸入将是非常有害的，即便穿着了防护服之后也是如此，因为月尘会附着在宇航服上被带回生活舱内。而一旦被吸入肺内，这些超微细，拥有尖锐棱角的月尘就会引起一系列的负面效应，引起呼吸系统和心血管系统的问题，引起呼吸道肿胀，并增加患各种癌症的风险。这些月球尘埃已经经受了上百万年的紫外线辐射，它们进入人体后会深入肺部，而月面上的低重力环境也只会帮助这些尘埃更加容易地深入身体组织。 除此之外，这些月尘的棱角锋利如玻璃，由于没有地球上那样经年累月的侵蚀作用，这些月尘棱角尖锐，因此很容易造成人体眼睛或皮肤的损害。而眼睛瘙痒在地球上或许只是一个小小的麻烦，但在执行太空任务时却有肯能酿成严重后果。 不过现在，在月面上行走从来都不是人们长期计划中的一项，因为呼吸氧气的问题才是更加主要的关注点。然而这些遍布的月尘，对于我们欣赏月球壮阔的景致，以及未来月球基地的建立，都将带来负面的影响。(晨风) 原文： http://www.dailymail.co.uk/sciencetech/article-2173172/The-Moon-layered-dust-bathed-radiation-prove-deadly-pioneers.html Earth's friend, Man's enemy: The Moon is layered in dust bathed in radiation, which could prove deadly for pioneers By Eddie Wrenn Living on the moon is surely humanity's goal as we make our first baby steps into space. But our constant neighbour may not treat us so well - for scientists now think that the very dust on our luna partner is poisonous to humans. The surface of the moon is coated in a layer of thick, undisturbed dust, which is not only ultra-fine - and therefore easy to inhale - but can increase the risk of various cancers, similar to breathing asbestos and volcanic ash. Researchers from the University of Tennessee, referring to Neil Armstrong's first steps onto the moon, said: 'The Apollo astronauts reported undesirable effects affecting the skin, eyes and airways that could be related to exposure to the dust that had adhered to their space suits during their extravehicular activities and was subsequently brought into their spacecraft.' Humans have only spent, at max, two or three days on the moon in total, and this time has often been spent in spaceships or airtight suits. But with long-term exposure, the team says that inhalation would be harmful - even when wearing protective gear, as dust trails the astronauts back into living quarters. Once inside the lungs the super-fine, sharp-edged lunar dust could health issues, affecting the respiratory and cardiovascular system, causing airway inflammation and increasing the risks of various cancers. The dust -subjected to millenia of UV radiation, would prentrate deep into the lungs, and micro-gravity would only help in bringing the dust deep into the lungs. ...And it's everywhere! Even the best cleaner in the world would be hard-pressed to remove all the dust from the moon's surface The sharp 'regolith' of the moon is also believed to be as sharp as glass, without years of erosion like on earth, causing skin and eye damage. And a scratched cornea, while perhaps just an irritant on Earth, could cause havoc on a space mission. Now, walking on the surface of the moon is never going to be in our long-term plans, as breathing is the primary issue. But the ever-constant dust of the moon may curtail our adventures into the stark grandness of the moonscape outside whichever space bases we build in the future.
标签: 人体
