The map distance between genes $A$ and $B$ is $3$ units, between $B$ and $C$ $10$ units and between $C$ and $A$ $7$ units. The order of the genes in a linkage map constructed on the above data would perhaps be
$A, B, C$
$A, C, B$
$B, C, A$
$B, A, C$
How many types of gametes will be produced by a $O$ Drosophila having following arrangement of
two genes ($y*$ and $w*$) on $X-$chromosome?
The distance between two genes in a chromosome is measured in cross-over units which represent
Morgan hybridised yellow-bodied, white-eyed females to brown-bodied, red-eyed males and intercrossed their $F_{1}$ progeny. He observed that
$(a)$ $F_{2}$ ratio was deviated very significantly from the $9 : 3 : 3 : 1$ ratio
$(b)$ Both genes did not segregate independently of each other
$(c)$ Recombinant types are not obtained in $F_{2}$ generation
$(d)$ Both genes segregate independently of each other
Select the correct set of statements :
Given below are two statements : one is labelled as Assertion $(A)$ and the other is labelled as Reason $(R)$.
Assertion $(A)$:
Mendel's law of Independent assortment does not hold good for the genes that are located closely on the same chromosome.
Reason $(R):$
Closely located genes assort independently.
In the light of the above statements, choose the correct answer from the options given below:
The linkage map of $X$-chromosome of fruit fly has $66$ units with yellow body gene $(y)$ at one end and bobbed hair $(b)$ gene at the other end. The recombination frequency between these two genes ($y$ and $b$) should be