Q. Human height is a multigenic character. If the heights of all the individuals living in a metropolis are measured and the percentages of the population belonging to a specific height are plotted as shown below, which of the plots would represent the most realistic distribution? image

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Solution:

In polygenic inheritance, a trait is controlled by more than one gene. Human height is a multigenic or polygenic trait, controlled by at least three genes with six alleles. Polygenic inheritance often results in a bell-shaped curve when you analyse the population. That means that most people fall in the middle of phenotypic range, such as average height, while very few people are at the extremes, such as very tall or very short. At one end of the curve will be individuals who are recessive for all the allels (for example aabbcc) at the other end will be individuals, who are dominant for all the alleles (for example AABBCC). Through the middle of the curve will be individuals who have a combination of dominant and recessive alleles (for example AaBbCc or AaBBcc). Thu