Determine the proportion of offspring phenotypes that would result when two merle dogs mate, if both dogs are heterozygous (ll) for the gene that regulates coat length.

75% would have the dominant traits for coat length, 25% would have recessive trait for coat length.

Explanation:

After completing a punnet square, we could find that our genotypes are 25% LL, 50% Ll, and 25% ll.

If these genotypes were to be physically expressed, LL and Ll would both be expressed as showing the dominant trait.

This means that 75% would have the dominant traits for coat length and 25% would have recessive trait for coat length.

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