Question

Which of the following statements are correct?
(a) Energy flow from producers to consumers is unidirectional
(b) Energy pyramid can never be inverted
(c) Transfer of energy follows the 1% law
Choose the correct answer from the options given below :

• A. (b) and (c) only
• B. (a), (b) and (c)
• C. (a) and (b) only
• D. (a) and (c) only

Hint:

Pyramids of biomass and numbers can occasionally be inverted (e.g., in deep marine ecosystems or a single-tree ecosystem). However, the pyramid of energy is strictly upright in all ecosystems due to the laws of thermodynamics.

Answer 1

The Correct Option is C

Step 1: Read the statements.
We must find which are correct: (a) energy flow from producers to consumers is unidirectional, (b) the energy pyramid can never be inverted, (c) energy transfer follows the 1% law.
Step 2: Test (a).
Energy captured by producers flows one way up the trophic levels and cannot return. So (a) is correct.
Step 3: Test (b).
Because energy is lost as heat at each level, higher levels always have less energy, so the energy pyramid is always upright and never inverted. So (b) is correct.
Step 4: Test (c).
Energy transfer between successive trophic levels follows the 10% law (Lindeman), not the 1% law. The 1% figure refers to how much solar energy plants capture, which is a different thing. So (c) is incorrect.
Step 5: Collect the correct ones.
Only (a) and (b) are correct.
Step 6: Conclude.
The correct combination is (a) and (b) only, which is option (3).
\[ \boxed{\text{(a) and (b) only}} \]