Auxetic growth is characterised by

Options

A. Increase in cell number
B. Growth without increase in cell number
C. Both increase in cell number and cell growth
D. Expansion in transverse direction

Answer

**Step-by-Step Solution:**

1. **Understanding Auxetic Growth**: Auxetic growth refers to a specific type of growth pattern observed in biological organisms. It is characterized by an increase in the size of cells rather than an increase in the number of cells.

2. **Identifying Key Characteristics**: In auxetic growth, the primary feature is that the cells expand in size. This means that while the overall mass or volume of the organism may increase, the actual number of cells remains constant.

3. **Examples of Auxetic Growth**: Auxetic growth can be observed in both plants and animals. In humans, for instance, muscle cells can exhibit auxetic growth when they increase in size due to exercise and hypertrophy without an increase in the number of muscle cells. In plants, auxin, a plant hormone, promotes cell enlargement, leading to auxetic growth.

4. **Conclusion**: Based on the characteristics and examples discussed, auxetic growth is best defined as "growth without an increase in cell number."

**Final Answer**: Auxetic growth is characterized by growth without an increase in cell number.

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