alleryStart learning →A Yy pea plant is self-crossed, with yellow dominant to green. What phenotypic ratio is expected in the offspring?
A3 yellow to 1 green
B1 yellow to 1 green
C1 yellow to 2 green
D2 yellow to 2 green
Answer & Solution
Correct answer: A. 3 yellow to 1 green
1. The two by two square for Yy crossed with Yy gives the boxes YY, Yy, yY and yy.
2. Y is dominant, so YY, Yy and yY all give yellow seeds, which is three boxes.
3. Only yy gives green seeds, which is one box.
4. Applying the sum rule to the yellow classes gives 1/4 plus 1/2, which is 3/4.
5. So the phenotypic ratio is 3 yellow to 1 green.
_Source: OpenStax Biology (1st ed., CC BY 4.0), Ch 12 "Mendel's Experiments and Heredity", section 12.2 Characteristics and Traits_
Keep practising Mendel's Experiments and Heredity
Browse all Mendel's Experiments and Heredity questions for NCEA Level 2, or explore more Biology topics.
Related questions
Sort each clue by its dominance patternOrder the steps of crossing overKnock out the false allele claimsHow many genes contribute to eye colour in humans, at minimum?A single characteristic gives a phenotypic ratio whose parts total 16. What does that usuaIn shepherd's purse, seeds are ovoid only when both genes are homozygous recessive. What rTwo mice heterozygous at both the A and C genes are crossed. What phenotypic ratio of agouAgouti coat colour needs a dominant A allele, but pigment of any kind needs a dominant C a