Answer the following questions based on Hershey and Chase.s experiments:
Why did they use two types of culture media to grow viruses in? Explain.

Answer the following questions based on Hershey and Chase.s experiments: Name the kind of virus they worked with and why?

Answer the following questions based on Hershey and Chase experiments: State the conclusion drawn by them after the experiments.

Answer the following questions based on Hershey and Chase.s experiments: What was the need for using a blender and later a centrifuge during their experiments ?

Which of the following isotopes were used in the Hershey-Chase experiments ?

Answer the following questions based on Meselson and Stahl s experiment: (a) Write the name of the chemical substance used as a source of nitrogen in the experiment by them. (b) Why did the scientists synthesise the light and the heavy DNA molecules In the organism used in the experiment ? (c) How did the scientists make it possible to distinguish the heavy DNA molecule from the light DNA molecule ? Explain. ((1) Write the conclusion the scientists arrived at after completing the experiment.

Answer the following questions based on Meselson and Stahl's experiment of E. coli : (a) Write the name of the chemical substance used as the only source of nitrogen in the experiment. (b) Why did they allow the synthesis of the light and the heavy DNA molecules in the organism ? (c ) How did they distinguish the heavy DNA molecules from the light DNA molecules? Explain. (d) Write the conclusion the scientists arrived at, at the end of the experiment.

Answer the following questions with reference to Millikan.s oil drop experiment: What is the use of an X-ray tube ?

Answer the following questions : Why are alkalis used in space shuttles .

Answer the following questions with reference to Millikan.s oil drop experiment: What is an atomiser ?

Answer the following questions : Name two bases which do not decompose on heating.