which ones are related

Options

A. dichasium and hypanthodium
B. verticillaster and spike
C. hypanthodium and catkin
D. umbel and corymb

Answer

To determine which terms are related in the context of inflorescence, we will analyze each option provided in the question step by step.

### Step 1: Analyze Option 1 - Dikacium and Hyponthodium
- **Dikacium**: This is characterized by the development of two lateral branches on either side of a terminal apical flower.
- **Hyponthodium**: This structure has a fleshy petal forming a hollow cavity with flowers developing on the inner wall of this cavity.

**Conclusion**: Dikacium and Hyponthodium are not related to each other.

### Step 2: Analyze Option 2 - Verticalis Cluster and Spike
- **Verticalis Cluster**: This consists of a cluster of scissile or sub-scissile flowers, arranged on a trisacchial axis, ending in a monoscia.
- **Spike**: In a spike, the peduncle bears bisexual and scissile flowers.

**Conclusion**: Verticalis Cluster and Spike are not related to each other.

### Step 3: Analyze Option 3 - Hyponthodium and Catkin
- **Hyponthodium**: As previously described, it has a hollow cavity with flowers on the inner wall.
- **Catkin**: This is characterized by a flexible spike that bears unisexual flowers, often found in leaf axils.

**Conclusion**: Hyponthodium and Catkin are not related to each other.

### Step 4: Analyze Option 4 - Umbil and Cryom
- **Umbil**: In this structure, the main axis is greatly reduced, and flowers arise from the same point.
- **Cryom**: Here, the main axis is short, and flowers are positioned at the same level.

**Conclusion**: Umbil and Cryom are related to each other as both have flowers that are positioned at the same level.

### Final Answer
The correct option that identifies related terms is **Option 4: Umbil and Cryom**.

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