In **co-dominance** (e.g. coat colour in cattle), the F₁ of a red × white cross is:
- Red
- White
- Roan (red AND white hair together)
- Pink
Show answer and solution
Correct answer: C. Roan (red AND white hair together)
**Co-dominance:** both alleles are expressed equally.
RR × WW gives F₁ RW = **roan** — coat has a mixture of red and white hairs (not blended pink).
F₂ ratio is 1 red : 2 roan : 1 white.
ABO blood groups (IA, IB co-dominant) are another classic example.