Observe the relationship between first two words and then fill the suitable word/words at the fourth place.
Leaves : Foliar transpiration :: Stem : ..................

Explanation

To solve the analogy "Leaves : Foliar transpiration :: Stem : ...", we need to understand the relationship between the first two terms and then apply that relationship to the second pair.

1. **Identify the relationship**: The first term is "Leaves" and the second term is "Foliar transpiration". Foliar transpiration refers to the process of water vapor loss from the leaf surfaces, primarily through stomata and cuticles.

2. **Analyze the second pair**: The first word in the second pair is "Stem". We need to find a term that describes the process of water vapor loss from the stem, similar to how foliar transpiration describes the process for leaves.

3. **Understand stem transpiration**: In stems, transpiration occurs through small pores called lenticels. These lenticels facilitate gas exchange and also contribute to water loss through transpiration.

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