Question
Biology Question on Principles of Inheritance and Variation
Which is a sex influenced trait ?
A
pattern baldness in man
B
hairy pinna
C
porcupine skin in man
D
colourblindness in man
Answer
pattern baldness in man
Explanation
Solution
Some genes may be present on autosomes or on sex chromosomes, but their expression is influenced by sex of the bearer which are called sex-influenced genes. Pattern baldness in human beings is an example of sex-influenced genes. The gene for baldness is found to be dominant in males and recessive in females whereas in heterozygous condition, it is expressed in presence of only male hormone.