Question

Sol.(b) [Key Concept: Incomplete Dominance — Molecular Basis] Incomplete dominance occurs when heterozygotes synthesise a REDUCED amount of the functional enzyme (or protein), producing an intermediate phenotype. For example, in Mirabilis jalapa: one R allele produces enough red pigment for full red colour (RR), one R allele in Rr produces half the amount → intermediate pink, and rr produces no pigment → white. The reduced gene dosage (one functional allele instead of two) results in intermediate phenotype.