H. An albino person married to a normal woman, and their children were all normal-skined. While 2 normal-skined parents produced an albino child. Explain that genetically.

i. On mating between a grey-coloured, and long-winged male Drosophila hybrid in the 2 characters with pure black-coloured, and vestigial-winged female. The produced generation are of the same phenotypes of the parents in the ratio 1:1. Explain that genetically.

J. Mother with blood group (B) gives birth for a child with blood group (A). Mention the possible genotypes of the 2 parents and the rest of their children on genetic basis.

k. On mating between a female Drosophila with grey colour and long wings and hybrid in the 2 characteristics with a male one black-coloured and vestigial-winged, the following offspring results:

- 415 grey, and long. – 415 black, and vestigial.

- 85 grey, and vestigial. – 85 black, and long.

(1) Explain these results genetically.

(2) Determine the location of the pairs of genes that control the 2 characteristics, whether they exist on the same pair of homologous chromosomes, or on different pairs of homologous chromosomes. Why?

(3) In case of their presence on the same pair of homologous chromosomes, determine the relative distance between these genes.

L. A narrow-eyed person married to a wide-eyed woman, and their children were all wide-eyed. While 2 wide-eyed parents produced a child with narrow eyes. Explain that genetically.

m. On carrying out some hybridization on Antirrhinum plants, it was found that:

- Crossing of white-flowered plants with red-flowered plants produce pink-flowered plants.

- Crossing of pink-flowered plants may produce some white-flowered and red-flowered plants.

Explain these results genetically.

n. How did Morgan succeed in obtaining female white-eyed Drosophila insects?

O. The environment has an effect on the genes and their characteristics. This was confirmed experimentally on both plants and animals. Mention three examples to represent this fact.

Question no.7

A. join a statement of column X with the suitable statement from column Y to form a complete sentence, and write it down:

XY