g****2
发帖数: 1 | 1 100%抄袭科学美国人文字
原文作者 Chao-Qiang Lai
Molecular biologist of the Jean Mayer
U.S. Department of Agriculture Human
Nutrition Research Center on Aging at
Tufts University
科学美国人英文原文
For example say a man 175 cm tall marriesa woman 165 cm tall and both
are from a Chinese population with a populationmean of 170 cm for men and
160 cm for women. We can predict the height of theirchildren assuming the
heritability is 65 percent for men and 60 percent forwomen in this
population. For a son the expected height difference from thepopulation mean
is: 0.65 x [(175 - 170) + (165 - 160)] / 2 which equals 3.25cm; for a
daughter the difference is 0.6 x [(175 - 170)
+ (165 - 160)] / 2which equals 3 cm. Thus the expected height of a son is
170 + 3.2 or 173.2cm
and of a daughter 160 + 3 or 163 cm. On the other hand environmentaleffects
can add 1.75 cm to a son""""s height: 0.35 x [(175 - 170) + (165 - 160)] /2
and 2 cm to a daughter""""s:
0.4 x [(175 - 170) + ( 165 - 160)] / 2. Of coursethese predictions only
reflect the mean expected
height for each of the twosiblings (brothers and sisters); the actual
observed height may be different.
方舟子 《身高的烦恼》中文
假定一个身高1.75米的中国男子和一个身高1.65米的中国女子结婚，如果生的是儿子，
我们可以预测遗传因素会让他比平均身高高出0.65 x [(175 - 170) +(165 - 160)] /2
=3.25厘米，如果生的是女儿的话，则是0.6 x [(175 -170) + (165 - 160)] / 2 =3
厘米。环境因素有可能会让儿子再高出0.35 x[(175 - 170) + (165 - 160)] / 2 =
1.75厘米，女儿高出0.4x[(175 - 170) + (165 - 160)] / 2 =2厘米。当然这只是平均
值，实际情形会有所差异。如果加强营养，则有可能让子女长得比父母高。影响身高的
最重要的营养素是蛋白质，其次是钙等矿物质和维生素D、A。 |
g****2
发帖数: 1 | 2 Wiki 英文原文
Humans grow fastest(other than in the womb) as infants and toddlersrapidly
declining from a maximum at birth to roughly age 2 tapering to a slowly
declining rate and then during the pubertal growth spurt a rapid rise to a
second maxima (at around 11–12 years for female and 13–14 years for male)
followed by a steady decline to zero. On average female growth velocity
trails off to zero at about 15 or 16 years whereas the male curve continues
for approximately 3 more years going to zero at about 18–20. These are also
critical periods where stressors such as malnutrition (or
even severe child neglect) have the greatest effect
方舟子 《身高的烦恼》中文
身高的这种增长趋势，与营养的改善有关。生长最迅速的时期是新生儿和婴儿时期（0
～2岁），其次是青春期早期（女孩11～12岁，男孩13～14岁），这 两个时期的营养状
况对身高至关重要。但是一个人的身高同时也受遗传因素的影响，父母身材比较高的，
其子女往往也比较高。那么先天的遗传因素和后天的环境因 素对身材高低的影响哪个
更重要呢？我们可以通过统计亲属（特别是孪生子）的身高计算出遗传因素所占的比重
。如果在一个人群，所有的人都能获得生长所需的足 够营养，那么影响身高差异的主
要是遗传因素，例如美国人的身高80%受遗传因素的影响。
(In the U.S. the heritability of height was estimated as 80 percent for
white men. 美国白人变成了美国人，方博士读懂了没有) |
g****2
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g****2
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d****o
发帖数: 32610 | 5
【在 g****2 的大作中提到】
: 100%抄袭科学美国人文字
: 原文作者 Chao-Qiang Lai
: Molecular biologist of the Jean Mayer
: U.S. Department of Agriculture Human
: Nutrition Research Center on Aging at
: Tufts University
: 科学美国人英文原文
: For example say a man 175 cm tall marriesa woman 165 cm tall and both
: are from a Chinese population with a populationmean of 170 cm for men and
: 160 cm for women. We can predict the height of theirchildren assuming the
|
