The casparian strip affects
(a) how minerals but not water move
(b) how water and minerals move into the vascular cylinder
(c) neither the flow of water nor the flow of minerals into a plant
(d) how water but not minerals move

Options

A. how minerals but not water move
B. how water and minerals move into the vascular cylinder
C. neither the flow of water nor the flow of minerals into a plant
D. how water but not minerals move

Answer

To solve the question regarding the effect of the Casparian strip, let's break down the information step by step.

### Step-by-Step Solution:

1. **Understanding the Casparian Strip**:
- The Casparian strip is a band of waterproof tissue found in the endodermis of plant roots. Its primary function is to regulate the movement of water and minerals into the vascular cylinder.

2. **Function of the Casparian Strip**:
- It prevents water and dissolved minerals from passing freely into the vascular cylinder (the central part of the root that contains xylem and phloem). Instead, it forces these substances to pass through the cell membranes of the endodermis cells, allowing for selective absorption.

3. **Analyzing the Options**:
- (a) "how minerals but not water move" - This option is incorrect because the Casparian strip affects both water and minerals.
- (b) "how water and minerals move into the vascular cylinder" - This option is correct as it describes the function of the Casparian strip accurately.
- (c) "neither the flow of water nor the flow of minerals into a plant" - This option is incorrect since the Casparian strip does influence the flow of both.
- (d) "how water but not minerals move" - This option is also incorrect for the same reason as option (a).

4. **Conclusion**:
- Based on the analysis, the correct answer is **(b) how water and minerals move into the vascular cylinder**.

### Final Answer:
(b) how water and minerals move into the vascular cylinder.