Biotechnology has helped farmers to get pest resistant cotton crop. Explain the technique adopted along with its mode of action.

One of the main objectives of biotechnology is to minimize the use of insecticides on cultivated crops. Explain help of a suitable example how insect resistant crops have been developed using techniques of biotechnology.

"Species Bt Toxin gene is incorporated into cotton plant so as to control infestation of Bollworm". Mention the organism from which the gene was isolated and explain its mode of action.

Raman went to a hospital with his father to see his uncle who was admitted there because of some health problems. The doctor asked Raman to bring a particular injection to be given to his uncle. When Raman brought the injection, the doctor asked him to get the injection changed from the chemist. Raman insisted that it was the same injection as prescribed by him and its expiry date is also next year. But the doctor explained Raman that the injection has not been expired but it was not of compatible concentration as prescribed by him. Raman felt satisfied and got the injection changed Answer the following questions: What was the reason for asking Raman to get hte injection of compatible concentration?

"Plant breeding technique has helped sugar industry in North India" Explain.

Name the insect that attacks cotton crops and causes lot of damage to the crop. How has Bt cotton plants overcome this problem and saved the crop? Explain.

How has the mutation breeding helped in improving crop varieties? Give one example where this technique helped.

Eels are able to generate current with biological cells called electroplaques. The electroplaques in an eel are arranged in 100 rows, each row stretching horizontally along the body of the fish containing 5000 electroplaques. The arrangment is suggestively shown below. Each electroplaques has an emf of 0.15 V and internal resistance of 0.25 Omega The water surrounding theeel completes a cricuit be ween the head and its tail. If the water surrounding it has a resistance of 500 Omega , the current an eel can produce in water is about

Sanya has a piece of land which is in the shape of a rhombus (See Fig. ). She wants her four children to work on the land and produce different crops to suffice the needs of their family. She divided the land in four parts by joining its opposite comers. If the perimeter of the land is 400 m and one of the diagonals is 160 m, how much area each child will get to work on.

Sanya has a piece of land which is in the shape of a rhombus (See Fig. ). She wants her one daughter and one son to work on the land and produce different crops to suffice the needs of their family. She divided the land in two parts by joining its opposite comers. If the perimeter of the land is 400 m and one of the diagonals is 160 m, how much area each of them will get to work on.

A square loop of side 12 cm with its sides parallel to X and Y axes is moved with a velocity of 8 cm s^-1 in the positive x-direction in an environment containing a magnetic field in the positive z-direction. The field is neither uniform in space nor constant in time. It has a gradient of 10^-3T cm^-1 along the negative x-direction (that is it increases by 10^-3T cm^-1 as one moves in the negative x-direction), and it is decreasing in time at the rate of 10^-3T cm^-1 . Determine the direction and magnitude of the induced current in the loop if its resistance is 4.50 mOmega .