Molecular Basis of Inheritance — BIOLOGY STD 12 Science — Question

1. Select the homologous structures from the combinations given below:

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

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

Give reasons why the human testes are located outside the abdominal cavity.

How many microsporangia are present in a typical anther of an angiosperm?

List and describe any two vegetative propagules in flowering plants.

Name important defence mechanisms in plants against herbivory.

The following statements (i), (ii) and (iii) seem to describe the waterpollinated submerged plants. Which one of these statements is incorrect?

1. The flowers do not produce nectar.
2. The pollen grains have mucilaginous covering.
3. The brightly coloured female flowers have long stalk to reach the surface.

1. What is a plasmid?
2. What is meant by ADA deficiency? How is gene therapy a solution to this problem? Why is it not a permanent cure?

Why is mother's milk considered the most appropriate food for a new born infant?

Which genes have been introduced in transgenic fish?

ELISA technique is based on the principles of antigen-antibody interaction. Can this techique be used in the molecular diagnosis of a genetic disorder, such as phenyketonuria?