Question

Assume that hair colour in humans is governed by a gene. If black hair are dominant over brown hair, then which letter correctly represents the dominant and the recessive trait respectively?

• A. B and B
• B. b and b
• C. b and B
• D. B and b

Answer 1

The correct option is D B and b

Dominant traits are represented by uppercase letters, while recessive traits are generally represented by lowercase. So, we can say that B denotes the dominant trait and b denotes the recessive trait. As black hair are dominant over brown hair, we can assume the possible genotypes for black hair to be BB or Bb. Likewise the genotype for brown hair will be bb.