Question

Which of the following statements are incorrect?
(i) A dominant allele determines the phenotype when paired with a recessive allele.
(ii) A recessive allele is weaker than a dominant allele.
(iii) A recessive allele does not show its effects when paired with a dominant allele.
(iv) A dominant allele is always better for an organism.

(A) (ii), (i) and (iv)
(B) (ii) and (iv)
(C) (i), (ii) and (iii)
(D) (i), (iii) and (iv)

Answer 1

Hint: The study of a specific trait that is passed down from one generation to the next is called pedigree analysis. Knowing whether a specific characteristic is genuinely inherited or not, as well as the trait's inheritance pattern, is helpful.

Complete Step by Step Answer:
Dominant/recessive interactions are the most frequent type of allele-allele interaction. When one (dominant) allele of a gene effectively outweighs the other (recessive) allele, the allele is said to be dominant. Blood types and eye color are two instances of dominant/recessive gene interactions.
Step by step solution: Alleles are two distinct variations of a same gene. They share the same chromosomal location. These run in the family. In a child, one allele is passed down from the father and the other from the mother. They encode various protein isoforms. They are either recessive or dominant. Only one copy is necessary for the expression of the dominant allele, which results in the dominant phenotype. A recessive allele needs two copies to manifest. The dominant allele is not stronger than the recessive allele. Due to altered or distinct "enzymes," it (the recessive allele) does not manifest its effects (in the presence of the dominant allele). Even when combined with the dominant allele, a recessive allele produces its gene product. It's not always preferable to have a dominant allele (in the case of dominant disease).
So, option (B) is the correct answer.

Note: A dominant allele, which can come from just one parent, causes a dominant phenotype in those who possess one copy of the gene. A person needs two copies of a recessive allele, one from each parent, in order for it to result in a recessive phenotype.