Answers

Answers

1. a) Genotypic and Phenotypic ratio

SS –1 (lethal), S+ - 2 (saddle back) and + + -1 (normal)

b) S+ -1, + + -1 (saddle back : normal, 1:1 )

c) All ++ (All normal )

2. By crossing a light coloured and normal pigmented common carp the F1 produced will be having light coloured and normal pigmentation in equal proportion.

3. a) leather x mirror

Phenotypic ratio – leather : scattered mirror (1:1)

Genotypic ratio – ssNn : ssnn (1:1)

b) leather x leather

Phenotypic ratio – 1 lethal : 2 leather : 1 scattered mirror

Genotypic ratio – 1 ssNN : 2 ss Nn : 1 ssnn

c) scaled x leather

Phenotypic ratio – linear mirror : scaled (1:1)

Genotypic ratio Ss Nn : Ssnn (1:1)

d) linear mirror x leather

Phenotypic ratio – 2 death : 2 linear mirror : 1 scaled :

2 leather : 1 scattered mirror

e) Linear mirror x linear mirror

Phenotypic ratio : 4 death : 3 scaled : 6 linear mirror :

2 leather : 1 scattered mirror

Genotypic ratio – 1 SSNN : 1 SSNn : 2 SsNN :5 SsNn :

1 SSnn : 2 Ssnn : 1 ssNN : 2 ssNn:

1 ssnn

f) scattered mirror x scattered mirror

Phenotypic ratio – All scattered mirror

Genotypic ratio – All ssnn

4. a) 12 dark : 3 light :1 albino

b) 2 dark : 1light :1 albino

c) All dark

d) All dark

e) All dark

Last modified: Tuesday, 29 November 2011, 6:01 AM