Pyramid of Energy in Terrestrial Ecosystems

Q. “The pyramid of biomass can be inverted but the pyramid of energy is always upright.” Justify. [3 marks]

Q.

Write important features of a sedimentary cycle in an ecosystem.

Q.

Which ecological pyramid can never occur in an inverted form?

Q. Pyramid of numbers in a forest ecosystem is spindle shaped.

1. True
2. False

Q.

(a) Name an ideal pyramid existing in an ecosystem. Construct it up to its three trophic levels along with their names.

(b) The sun provides 1, 000, 000 J of sunlight (solar energy) to an ecosystem. Write the amount of energy that is available to the first and third trophic levels respectively. [3 marks]

Q. Which of the following pairs has a sedimentary type of biogeochemical cycle?

1. Oxygen and nitrogen
2. Phosphorus and sulphur
3. Phosphorus and nitrogen
4. Phosphorus and oxygen

Q. Pyramid of numbers in a forest ecosystem is spindle shaped.

1. True
2. False

Q. An ecosystem has only one huge banyan trees. If I draw a pyramid, indicating the number of organisms in this ecosystem, what would it be like?

1. Inverted
2. Spindle shaped
3. Upright
4. Both A and B

Q.

Which one of the following statements for the pyramid of energy is incorrect?

1. Its base is broad

2. It shows energy content of different trophic level organisms

3. It is upright in shape

4. It is inverted in shape

Q. The pyramid shows the relative biomass of zooplankton and phytoplankton in a marine ecosystem.
The biomass of the zooplanktons is higher than that of the phytoplanktons because

1. The zooplanktons convert energy more efficiently
2. The zooplanktons have a shorter life cycle than the phytoplanktons
3. The phytoplanktons are individually much smaller than the zooplanktons
4. The phytoplanktons have an extremely high turnover rate

Q. Which ecological pyramid is always upright?

1. Pyramid of biomass
2. Pyramid of energy
3. Pyramid of number
4. Both a and c

Q.

The pyramid of energy in a terrestrial ecosystem is

1. upright

2. inverted

3. spindle shaped

4. irregular

Q.

Which one of the following is not a gaseous biogeochemical cycle in an ecosystem?

1. Phosphorus cycle

2. Oxygen cycle

3. Nitrogen cycle

4. Carbon cycle

Q. When charcoal is prepared from a living tree, it shows a disintegration rate of 15.3 disintegrations of ¹⁴C per gram per minute. A sample from an ancient piece of charcoal shows ¹⁴C activity to be 12.3 disintegrations per gram per minute. How old is this sample? Half-life of ¹⁴C is 5730 y.

Q. Which one of the following statements for the pyramid of energy is incorrect, whereas the remaining three are correct?

1. It is upright in shape
2. Its base is broad
3. It shows energy content of different trophic level organisms
4. It is inverted in shape

Q. Assertion :During succession, nutrient availability decreases while biomass level increases. Reason: NCP decreases during succession.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q. The efficiency of any ecosystem is best depicted by pyramid of

1. Energy
2. Number
3. Biomass
4. Volume