The genotypic ratio of the Mendel's law can be expressed by

( a ) $(a+bx)^2$
( b ) $(ax+by)^2$
( c ) $(ax+b)^2$
( d ) $(ax+by)^3$

Ans: B: $(ax+by)^2$
Based on $\frac {1}{4} : \frac {1}{2} : \frac {1}{4}$ ratio of TT : Tt : tt, it can be mathematically condensed to the form of a binominal expression $(ax + by)^2$, that has gametes bearing genes T or t in equal frequency of $\frac {1}{2}$.
The expanded form of the expression is:
$(\frac{1}{2}T + \frac {1}{2} t)^2 = (\frac {1}{2}T + \frac {1}{1}t) \times (\frac {1}{2}T + \frac {1}{2}t)$
$= \frac {1}{4} T^2T + \frac {1}{2} T t^2 + \frac {1}{4} tt$
answered Dec 27, 2016
edited Dec 27, 2016