Question

The pyramid of number in the grassland ecosystem is
A. Always erect
B. Always inverted
C. Either erect or inverted
D. Irregular

Answer 1

Hint: The pyramid of numbers is based on the number of producers, herbivores, carnivores, scavengers, etc .that are present at the successive trophic levels.

Complete answer:
To solve this question, we must know how the pyramid of numbers is represented in the grassland ecosystem.
In any grassland ecosystem, the producers will always be the green plants. In any grassland green plants will always be in abundance. Then the number of herbivores will be less than the producers. The carnivores will further be less in number. Hence the pyramid of numbers in the grassland ecosystem will always be erect and upright.
  Further, the pyramid of numbers for parasitic food chains is inverted. This is so because the tree is assumed to be the producer. The fruit eating -birds are considered to be the herbivores which are more in number. Then the lice and bugs present on the birds are furthermore in number. Finally the hyper-parasites on lice and bugs are innumerable. Hence, the pyramid of numbers in the parasitic food chain is inverted.
Since, now we know about the various food chains, therefore, the correct answer to this question is that the pyramid of numbers in the grassland ecosystem is always erect.

Note:
1. The pyramid of numbers in a forest ecosystem is intermediate.
2. Number of producers per unit area in a pond ecosystem is more than the ones present in the grassland ecosystem.