Question Bank [2022] — BIOLOGY STD 12 Science — Question

Write the types of sex-determination mechanisms the following crosses show. Give an example of each type.

1. Female XX with male XO
2. Female ZW with male ZZ.

State what is out-crossing type of breeding. Mention on what type of cattle this is practised.

What is meant by the following:
Somaclones.

Mention two advantages of seeds to man.

Explain the permanent methods of birth control.

Satish is a colourblind boy. His mother has normal vision but his maternal grandfather is colourblind. His father and maternal grandmother have normal vision. Explain the pattern of inheritance with a suitable chart.

Is there a relationship between the size of an organism and its life span? Give two examples in support of your answer.

Estuarine waters, Taiga, Aquarium tank, Lake, Evergreen forest, Flower garden.

Types of ecosystems	Examples
(1) Aquatic	________________
(2) Terrestrial	________________
(3) Artificial	________________

Benzyl penicillin, Chloromycetin, Mebendazole, Levamisole, Pyrimethamine Ampicillin, Ty21a vaccine, Sulfadoxine.

Column A (Disease)	Column B (Treatment)
(1) Pneumonia	————–
(2) Malaria	————–
(3) Ascariasis	————–
(4) Typhoid	————–

Explain the mechanism of sex determination in insects like Drosophila and grasshopper.