Branching is inhibited by __ from the tip of a growing shoot, but this effect is encountered by. from the root

Options

A. Cytokinin, auxin
B. Auxin, Cytokinin
C. GA, Cytokinin
D. GA, ABA

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which hormone inhibits branching from the tip of a growing shoot and which hormone counters this effect from the root.

2. **Identifying the Inhibiting Hormone**: The hormone that inhibits branching is known as auxin. Auxin is produced at the tips of shoots and is responsible for apical dominance, which prevents lateral branching.

3. **Identifying the Counteracting Hormone**: The hormone that counters the effect of auxin and promotes branching is cytokinins. Cytokinins are produced in the roots and help to promote cell division and growth, thereby overcoming the apical dominance exerted by auxin.

4. **Filling in the Blanks**: Based on the information gathered:
- The first blank (inhibiting hormone from the tip of a growing shoot) is filled with "auxin."
- The second blank (hormone from the root that encounters the effect of auxin) is filled with "cytokinins."

5. **Final Answer**: Therefore, the complete answer to the question is: "Branching is inhibited by auxin from the tip of a growing shoot, but this effect is encountered by cytokinins from the root."

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