Blood does not clot in the blood vessels due to the presence of 

' Lockjaw ' is the last phase of which of the following diseases ? 

Which of the following elements does not spread pollution?

The Base event in protein synthesis produces a ……………….

The colour of the ocean appears to be blue because the sunlight falling on it is-

An organism which can monitor air pollution is –  

The atoms of Germanium, Arsenic, Selenium and Bromine contain _____ shells.