Biotechnology and its Applications — BIOLOGY STD 12 Science — Question

A student on a school trip started sneezing and wheezing soon after reaching the hill station for no explained reasons. But, on return to the plains the symptoms disappeared. What is such a response called? How does the body produce it?

Draw a labelled sketch of sparged-stirred-tank bioreactor. Write its application.

What will happen to an ecosystem if:
All producers are removed.

Name the type of interaction seen in each of the following examples:

1. Ascaris worms living in the intestine of human.
2. Wasp pollinating fig inflorescence.
3. Clown fish living among the tentacles of sea-anemone.
4. Mycorrhizae living on the roots of higher plants.
5. Orchid growing on a branch of a mango tree.
6. Disappearance of smaller barnacles when Balanus dominated in the Coast of Scotland.

Are there any homologous organs in male and female reproductive system? If yes, give examples.

Gene A, B, C and D are linked. By carrying breeding experiment and recording offspring phenotype the following cross over frequencies are determined.

What is the order of the genes on the linkage map?

Write the important functions of various reproductive organs of human female.

Fertilisation is essential for production of seed, but in some angiosperms, seeds develop without fertilisation.
Explain the two ways by which seeds develop without fertilisation.

Identify A, B, C and D in the table given below:

Micro-organism	Product	Biological activity	Medical ailment/ Procedure
A	Streptokinase	Clot buster	D
Trichoderma	B	C	Transplant
Polysporum			Surgery

1. Sickle celled anaemia in humans is a result of point mutation. Explain.
2. Write the genotypes of both the parents who have produced a sickle celled anaemic offspring.