Growth is defined as

Options

A. increase in size only.
B. increase in shape only.
C. increase in weight only.
D. permanent irreversible increase in size which occurs in cells or organs or organism.

Answer

**Step-by-Step Text Solution:**

1. **Understanding Growth**: Growth in biological terms refers to an increase in size, which can occur at the cellular level. It involves both cell division (the process by which a cell divides to form new cells) and cell enlargement (the process by which cells increase in size).

2. **Characteristics of Growth**:
- Growth is an irreversible process, meaning once an organism has grown, it cannot return to its original size or state.
- It is a permanent change that occurs in organisms over time.

3. **Evaluating the Options**:
- **Option 1**: "Increase in size only" - This is incorrect because growth also involves changes in other aspects, not just size.
- **Option 2**: "Increase in shape only" - This is also incorrect as growth is not limited to shape changes.
- **Option 3**: "Increase in weight only" - This is incorrect as well; growth encompasses more than just weight.
- **Option 4**: "Permanent irreversible change or increase in size which occurs in cells or organs or organisms" - This option accurately describes growth, as it includes the essential characteristics of being permanent and irreversible.

4. **Conclusion**: Based on the evaluation of the options, the correct definition of growth is given by Option 4.

**Final Answer**: Growth is defined as a permanent irreversible change or increase in size which occurs in cells or organs or organisms.

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