Question

In some goats, the presence of horns is produced by an autosomal allele that is dominant in males and recessive in females. A horned female is crossed with a hornless male. One of the resulting F1F1 females is crossed with a hornless male. Then

• A. All male progeny and none of the female progeny will be horned
• B. All female progeny and none of the male progeny will be horned
• C. $50\%$ of the male progeny and none of the female progeny will be horned
• D. $50\%$ of the female progeny and none of the male progeny will be horned

Answer 1

Answer: (C)

$50\%$ of the male progeny and none of the female progeny will be horned

For females, both the alleles should have the horned character to express the horned phenotype and for males, it is a dominant feature as a result of which only one horned allele is enough to express the horned phenotype.
The Punnett square below shows the cross between a horned female is crossed with a hornless male:-

Female/ Male	XH	XH
X	XXH	XXH
Y	YXH	YXH

After the F1 progeny female is crossed with a hornless male, the following Punnett square will be brought into effect:-

Female/ Male	XH	X
X	XXH	XX
Y	YXH	XY

So the correct option is '50% of the male progeny and none of the female progeny will be horned'.