Consider the given two statements:

I:	In most ecosystems, all the ecological pyramids are largely upright.
II:	Pyramid of energy can be a notable exception to the above rule.

1. Both I and II are correct.
2. Both I and II are incorrect.
3. Only II is correct.
4. Only I is correct.

Primary succession takes a very long time when compared to secondary succession, primarily, because:
1. immigration of pioneer species takes time
2. soil formation is a very slow process
3. there is a low availability of ecological niches
4. environmental conditions are highly variable

Energy flow and nutrient cycling are two important components of an ecosystem. What will be true comparison of the two?

The ecological pyramids that can never be inverted in a natural ecosystem include:

1. Only II
2. Only III
3. Only II and III
4. All can be inverted

In an open ocean, the pyramid of biomass is often inverted. How can this support higher trophic levels?

An important feature of the phosphorus cycle is that its reservoir is in:
1. aquifers
2. soil and rocks
3. the atmosphere
4. the sun

Net primary productivity is the gross primary productivity minus:

Climax community is in a state of :
1. Non-equilibrium
2. Equilibrium
3. Disorder
4. Constant change

During the process of ecological succession, the changes that take place in communities are :
1. Orderly and sequential
2. Random
3. Very quick
4. Not influenced by the physical environment

Pyramid of numbers is :
1. Always upright
2. Always inverted
3. Either upright or inverted
4. Neither upright nor inverted