Given below is a schematic diagram showing Mendel's Experiment on sweet pea plants having axial flowers with round seeds (AARR) and Terminal flowers with wrinkled seeds (aarr). Study the same and answer the questions that follow :
(i) Give the phenotype of $F_{1}$ progeny.
(ii) Give the phenotype of $F_{2}$ progeny produced upon by the self-pollination of $F_{1}$ progeny.
(iii) Give the phenotype ratio of $F_{2}$ progeny.
(iv) Name and explain the law induced by Mendel on the basis of the above observation.

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Solution

(i) The phenotype of F $_{1}$ progeny will be Axial Round as it is dominant phenotype.
(ii) The phenotypes of F $_{2}$ progeny will be Axial Round, Axial Wrinkled, Terminal Round and Terminal Wrinkled as in F $_{2}$ generation, recessive trait is also expressed.
(iii) Phenotypic ratio of F $_{2}$ progeny will be 9:3:3:1.
(iv) Above observation are based on Law of Independent Assortment. This law states that factors or genes controlling different characters assort independently without influencing each other during the formation of gametes.

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A cross was made between pure breeding pea plants, one with round and green seeds and the other with wrinkled and yellow seeds.

(a) Write the phenotype of

F_{1}

progeny. Give reason for your answer.

(b) Write the different types of

F_{2}

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F_{1}

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Q. A homozygous plant having round (R) and yellow (Y) seed is crossed with the homozygous plant having wrinkled (r) and green (y) seeds. Answer the following questions based on observation.
i) Give the scientific name of the plant on which Mendel conducted his hybridization experiments.
ii) Give the genotype of the

F_{1}

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iii) Give the dihybrid phenotypic ratio and the phenotype of the offspring of the

F_{2}

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F_{1}

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iv) Name and state the law which explains the dihybrid ratio.
v) Give the possible combinations of gametes that can be obtained from

F_{1}

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Mendel first crossed pure-bred pea plants having round -yellow seeds with pure-bred pea plants having wrinkled -green seeds and found that only round- yellow seeds were produced in the $F_{1}$ generation. When $F_{1}$ generation pea plants having round-yellow seeds were cross-bred by self-pollination, then peas having round-yellow seeds, round green seeds, wrinkled-yellow seeds and wrinkled -green seeds were produced. Mendel collected a total of 2160 seeds.

(a) What will be the number of (i) round green seeds (ii) wrinkled green seeds (iii) round yellow seeds, and (iv) wrinkled-yellow seeds?

(b) Which 'ratio' as established by Mendel have you made use of in answering the part (a) above?

Q. In an experiment on pea plant, pure plants with yellow round seeds (YYRR) were crossed with plants producing green wrinkled seeds (yyrr). What will be phenotypic ratio of

F_{1}

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Q. A pea plant with round seeds having large starch grains is crossed with another pure pea plant with wrinkled seeds having small starch grains. The

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