When Dominance Breaks

40 questions on this block. Tap an answer and it moves on by itself — correct answers advance immediately, misses hold a few seconds so you can read why.

One question separates the two hard patterns Is the middle phenotype a NEW colour, or BOTH colours at once? A new colour is incomplete dominance. Both at once is codominance.

Warm-up · not scored

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Cross two heterozygotes: complete dominance gives 3 : 1, but incomplete dominance and codominance give 1 : 2 : 1 with three phenotypes.

Part 1Two phenotypes or three

Part 2Incomplete dominance

Part 3Codominance

Part 4Telling them apart

Part 5Multiple alleles and blood type

Part 6Superscripts and mixed practice

When Dominance Breaks

Warm-up · not scored

Review Complete

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