How many gametic combinations would be possible if a human individual were heterozygous for 23 genes on 23 different chromosomes?

Solution:

if a human individual were heterozygous for 23 genes on 23 different chromosomes the following gametic combination is possible:

With respect to chromosome is 1 then, the individual can produce 2 kinds of gametes. With respect to chromosome number 2, also 2 kinds. So, the equation is:  

Number of different gametes = 2^n where n is the number of chromosomes. So,  

2^23 = 8.4X10^6 different gametes.

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