Growth of a pollen tube is measured in terms of it's

Answer

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

1. **Understanding the Pollen Tube Formation**: When pollen grains land on the stigma of a flower, they germinate and form a pollen tube. This tube grows down through the style towards the ovule.

2. **Pollen Tube Growth**: The growth of the pollen tube is crucial for fertilization as it carries male gametes to the ovule. Multiple pollen grains can land on the stigma, but only one pollen tube typically fertilizes the ovule.

3. **Measuring Growth**: The growth of the pollen tube can be quantified and compared. The primary measure of growth in this context is the length of the pollen tube.

4. **Conclusion**: Therefore, the growth of a pollen tube is measured in terms of its length.

**Final Answer**: The growth of a pollen tube is measured in terms of its length.

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