More than two leaves arise at each node and more than two branches arise at a time on a peduncle in these genera respectively

Options

A. Alstonia, Nerium
B. Nerium, Alstonia
C. Nerium, Ipomoea
D. Sunflower, carrot

Answer

To answer the question regarding the genera where more than two leaves arise at each node and more than two branches arise at a time on a peduncle, we can break down the solution into the following steps:

### Step-by-Step Solution:

1. **Understanding the Terms**:
- **Node**: A point on a stem where leaves are attached.
- **Peduncle**: The stalk that supports a flower or flower cluster.
- **Phyllotaxy**: The arrangement of leaves on a stem.

2. **Identifying the First Condition**:
- The first condition states that more than two leaves arise at each node. This is indicative of a specific type of phyllotaxy.
- The type of phyllotaxy where multiple leaves emerge from a single node is called **whorled phyllotaxy** (or **verticillate**).
- An example of a plant exhibiting whorled phyllotaxy is **Alstonia**.

3. **Identifying the Second Condition**:
- The second condition mentions that more than two branches arise from a single peduncle.
- This is observed in plants that produce a cluster of flowers, where multiple branches emerge from one stalk.
- An example of such a plant is **Nerium**, which has a peduncle that supports multiple branches leading to a dense cluster of flowers.

4. **Conclusion**:
- Therefore, the two genera that meet the conditions specified in the question are **Alstonia** for the whorled phyllotaxy (more than two leaves at each node) and **Nerium** for the branching from the peduncle (more than two branches at a time).

### Final Answer:
The genera that exhibit the specified characteristics are **Alstonia** (for more than two leaves at each node) and **Nerium** (for more than two branches arising from a peduncle).

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