Biodiversity an...

Which of the following can solely keep an ecosystem self-sustaining and viable

Alpha diversity will describe 

Which of the benefits, wetlands provide

Out of the following which one will not represent an alternative way to categories ecosystem diversity:

keystone species include 

Polyps and medusae of coelenterates (fixed and free-floating stages) are examples of polymorphism related to 

If snakes become extinct :
i). The loss will make the bionetwork imbalanced
ii). Their gene pool will be lost forever
iii). Result will be loss of biodiversity

Rare species are :
i. represented by small populations in the world.
ii. thinly distributed over a wide area.
iii. all are grouped as endangered or vulnerable at present.

Assertion: The pattern of species diversity on earth is not uniformly distributed.
Reason: Species variation is generally highest in the tropics and decreases towards the poles.