During adverse season, therophytes survive by

The instrument which measures wind velocity is

Which one of the following words has been used by Prof. R. Misra for ecosystem

Plants are killed in winter by frost

Give scientific reasons : Decomposer essential in nature.

$A$ : Different ecotypes of a species despite being genotypically different are interfertile.
$R$ : They are locally natural selections from a pool of genetic variations found in gene pool of a species.