Transpiration is the (A)____ of water by plants. It occurs mainly through the (B) ____ in the leaves.

Answer

**Step-by-Step Solution:**

1. **Understanding Transpiration:**
- Transpiration is defined as the process through which plants lose water. This loss primarily occurs in the form of water vapor.

2. **Identifying the Process:**
- The key aspect of transpiration is the loss of water. Therefore, for blank (A), we can conclude that the correct term to fill in is "loss."

3. **Location of Transpiration:**
- Transpiration mainly occurs through specific structures in the leaves. These structures are known as stomata.

4. **Function of Stomata:**
- Stomata are tiny pores located on the surface of leaves. They play a crucial role in the transpiration process by allowing water vapor to escape from the plant.

5. **Role of Guard Cells:**
- Surrounding each stoma are guard cells, which regulate the opening and closing of the stomata. The turgidity (swelling) of these guard cells determines whether the stomata are open or closed.

6. **Finalizing the Answers:**
- Based on the above information, we can fill in the blanks:
- (A) "loss"
- (B) "stomata"

**Final Answer:**
Transpiration is the (A) **loss** of water by plants. It occurs mainly through the (B) **stomata** in the leaves.

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