Question

n mice, dwarfism is caused by an X-linked recessive allele, and pink coat is caused by an autosomal dominant allele (coats are normally brownish). If a dwarf female from a pure line is crossed with a pink male from a pure line, in the F2 generation, what will be the probability of getting a dwarf and pink female?

Answer 1

Answer:

The probability of getting a dwarf and pink female is 1/2

Explanation:

In mice, dwarfism is caused by an X-linked recessive allele, and pink coat is caused by an autosomal dominant allele where coats are normally brownish.

A dwarf female from a pure line will have Xd Xd where d represent the  recessive trait and the female is also brownish (pp).

A pink male from a pure line will be XPY where P represent the dominant allele but not a dwarf (D).

            Xd             Xd                            Xp          Xp

XD       XDXd        XDXd             XP    XPXp     XPXp    F1 generation

Y           XdY           XdY                Y     XpY        XpY

P        XDXd   x    XdY                        XPXp    x    XpY

           XD         Xd                               XP              Xp

Xd     XDXd    XdXd                  Xp    XPXp         XpXp         F2 generation

Y        XDY        XdY                   Y       XPY          XpY

The probability of getting a dwarf and pink female is 1/2