Which one of the following statement is correct w.a.t. growth?

Options

A. A unicellular organism does not grow
B. In plants, growth by cell division does not occur throughout their life span
C. In animals, the growth due to cell division is seen only upto certain age
D. Unicellular organism shows growth by cell elongation

Answer

To determine which statement is correct with respect to growth, let's analyze each option step by step.

### Step-by-Step Solution:

1. **Understanding Growth**:
- Growth is a fundamental characteristic of all living organisms. It is an intrinsic property, meaning it occurs from within the organism.

2. **Types of Growth**:
- Living organisms grow by increasing both their mass and the number of cells in their body. This growth is achieved through processes like cell division.

3. **Unicellular vs. Multicellular Organisms**:
- Both unicellular (like bacteria and amoeba) and multicellular organisms grow by cell division. Therefore, the statement that a unicellular organism does not grow is incorrect.

4. **Plant Growth**:
- Plants do grow throughout their lifespan, and this growth occurs through cell division and cell elongation. Thus, the statement that growth by cell division does not occur throughout their life span is also incorrect.

5. **Animal Growth**:
- In animals, growth due to cell division is indeed observed only up to a certain age, after which growth may slow down or stop. This statement is correct.

6. **Final Evaluation**:
- The correct statement regarding growth is: "In animals, the growth due to cell division is seen only up to a certain age."

### Conclusion:
The correct answer is option 3: "In animals, the growth due to cell division is seen only up to a certain age."

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