Consider the following statements
In an ecosystem energy
(i) Movement is unidirectional
(ii) Is lost irretrievably
(iii) Movement is non-cyclic
(iv) Movement is from higher to lower trophic levels
Of these statements

Options

A. (i), (ii) and (iii) are correct
B. (i) and (ii) are correct
C. (i), (iii) and (iv) are correct
D. (ii), (iii) and (iv) are correct

Answer

To solve the question regarding the statements about energy movement in an ecosystem, we will analyze each statement one by one:

### Step 1: Analyze Statement (i)
- **Statement (i): Movement is unidirectional.**
- In an ecosystem, energy flows in one direction, starting from the sun, to producers (plants), then to consumers (herbivores and carnivores), and finally to decomposers. This means that energy does not cycle back to the producers.
- **Conclusion:** This statement is **True**.

### Step 2: Analyze Statement (ii)
- **Statement (ii): Is lost irretrievably.**
- As energy flows through the ecosystem, a significant portion of it is lost as heat at each trophic level due to metabolic processes. This energy cannot be reused or retrieved.
- **Conclusion:** This statement is **True**.

### Step 3: Analyze Statement (iii)
- **Statement (iii): Movement is non-cyclic.**
- Energy does not cycle back in an ecosystem; it flows in a linear path from producers to various levels of consumers and eventually to decomposers.
- **Conclusion:** This statement is **True**.

### Step 4: Analyze Statement (iv)
- **Statement (iv): Movement is from higher to lower trophic levels.**
- Energy actually moves from lower trophic levels (producers) to higher trophic levels (consumers). Therefore, this statement is incorrect.
- **Conclusion:** This statement is **False**.

### Final Conclusion:
- Based on the analysis:
- Statements (i), (ii), and (iii) are **True**.
- Statement (iv) is **False**.

Thus, the correct statements regarding energy movement in an ecosystem are (i), (ii), and (iii).

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