求知渴望，没有答案不甘心

“儿子像妈， 女儿像爹”？  答案来了， Yes and No:

Y-chromosomes have fewer genes than X-chromosomes and some of them are responsible for the development of male genitals. This is why a boy is more likely to look like his mother. When it comes to girls, they receive X-chromosomes from both parents, so it's impossible to predict what they will look like.