Biotechnology: Principles and Processes — BIOLOGY STD 12 Science — Question

What are lifestyle diseases? How are they caused? Name any two such diseases.

Three water samples namely river water, untreated sewage water and Secondary effluent discharged from Sewage treatment plant were subjected to BOD test. The samples were labelled in A, B and C; but the laboratory attendant did not note which was which. The BOD values of the three samples A, B and C were recorded as 20 mg/L, 8mg/L and 400mg/L, respectively. Which sample of the water is most polluted? Can you assign the correct label to each assuming the river water is relatively clean?

Describe in brief Embryonic development after implantation.

The evolutionary story of moths in England during industrialisation reveals, that 'evolution is apparently reversible'. Clarify this statement.

Select the analogous structures from the combinations given below:

1. Forelimbs of whales and bats
2. Eyes of octopus and mammals
3. Tuber of sweet potato and potato
4. Thorns of Bougainvillea and tendrils of Cucurbita

2. ​​​​​​​State the kind of evolution they represent.

List any four symptoms of Down's syndrome. What is the basis of this disorder?

Geitonogamous flowering plants are genetically autogamous but functionally cross-pollinated. Justify.

What is the significance of progestogen oestrogen combination as a contraceptive measure?

All vertebrate embryos show some similarities at an early stage. Mention two such similarities. What do they indicate? Explain.

Write the use of the following in biotechnology.
Bioreactor.