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生物的雌雄比例称为性比,一般用100个雌体相对应的雄体的数目来表示,而植物则往往还可根据雌雄个体在100%中各自所占的比例体现出来。一、部分生物性比的统计数字国外对动植物种群的调查研究表明,绝大多数生物的雌雄比例接近1:1。从生态学角度说,如果两性个体的比例相差过分悬殊,就不利于种群的增殖。从遗传学方面看,XY型、ZW型以及XO型等性别类型的生物,只要形成配子的机会和配子结合的机会均等,其后代的雌雄比例,在理论上应该为1:1。但生物界中确实也存在不少雌雄比例相差悬殊的类型
The proportion of males to females is called the sex ratio, which is usually expressed as the number of males corresponding to 100 females, and the plants are often expressed in proportions of 100% of male and female individuals. First, the statistics of some biological ratios The survey of animal and plant populations abroad shows that the ratio of males to females of most organisms is close to 1:1. From an ecological point of view, if the proportion of the two sexes differs too widely, it is not conducive to population growth. In terms of genetics, the sex type organisms such as XY type, ZW type, and XO type, as long as the chance of forming gametes and the opportunity for gamete binding are equal, the ratio of male to female of their offspring should theoretically be 1:1. However, there are indeed many different types of male-female ratios in the biological world.