A transverse section of stem is stained first with safranin and then with fast green following the ususal schedule of double staining for the preparation of a permanent slide. What would be colour of the stained xylemand phloem?

Options

A. Red and green
B. green and red
C. orange and yellow
D. purple and orange.

Answer

To solve the question regarding the colors of stained xylem and phloem in a transverse section of a stem stained with safranin and fast green, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Stains**:
- Safranin is a red dye that is commonly used to stain plant tissues. It is known to preferentially stain certain tissues based on their chemical properties.
- Fast green is a green dye that is used in double staining techniques and typically stains other types of plant tissues.

2. **Identifying Xylem and Phloem**:
- Xylem is responsible for the transport of water and minerals from the roots to the rest of the plant. It typically contains lignin, which can interact with safranin.
- Phloem is responsible for the transport of nutrients, particularly sugars, throughout the plant. It contains different types of cells that are more neutral in pH.

3. **Staining Process**:
- When the transverse section of the stem is stained with safranin first, the xylem will absorb the safranin due to its chemical composition, resulting in a red color.
- After safranin, the section is stained with fast green. The phloem, being more neutral, will absorb the fast green dye, resulting in a green color.

4. **Final Color Identification**:
- Therefore, after the double staining process, the xylem will appear red due to safranin, and the phloem will appear green due to fast green.

5. **Conclusion**:
- The final answer is that the xylem will be stained red and the phloem will be stained green.

### Final Answer:
- Xylem: Red (from safranin)
- Phloem: Green (from fast green)

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