Answer: The role of an organism in the ecosystem is called its NICHE.
Explanation: The niche (pronounced 'neesh') of an organism is the specific function and purpose of the organism within its environment, ecosystem or food-web or food-chain.
The answer to this question is B
This is True . the reabsorption through the proximal tubule is obligatory 80% whereas water reabsorption through distal tubule is facultative but mostly through collector tubules 15 % ( under the action of aldosteron and antidiuretic hormone).