Suggest why dust that has been contaminated with Strontium-90 presents a serious health hazard.

Synthetic polymers are finding applications in almost all spheres of life and are making our life comfortable. Their large scale use has been based on their relative inertness to environment Process giving them durability for long time. However, their long durability is not altogether an advantage. These solid wastes remain undegraded for quite a long time and their disposal has created a serious problem of waste management. If the overuse of plastics continues, it will pose a serious threat to all of us. After reading the above passage, answer the following question : Is it advisable to continue with overuse of plastics due to their immense use in our daily life?

Why Trypanosoma has been placed in Kingdom Protista?

Why Drosphila has been used extensivley for genetical studies?

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?

Name the carcinogenic agent present in tobacco. Describe the health hazards of tobacco smoking.

Suggest the aspects of reproductive health which need to be given special attention to the present scenerio.

Why only Xe has been found to form some compounds amongst noble gases ?

A person in your colony has recently been diagnosed with AIDS. People/residents in the colony want him to leave colony for fear of spread of AIDS. List the possible preventive measures that you would suggest.

A solid metal sphere of radius r has charge +Q. This charge is one the surface of the sphere but it may be considered to be a point charge at its centre. Suggest, why your calculation in (a) for the metal sphere would not apply to a plastic sphere.