Spike with unisexual flowers is called.........

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the term used to describe a spike that contains unisexual flowers.

2. **Defining Spike**: A spike is a type of inflorescence where flowers are arranged along a central stem without any stalks.

3. **Identifying Unisexual Flowers**: Unisexual flowers are those that are either male or female, but not both.

4. **Inflorescence Types**: In the context of inflorescence, there are various types, and one specific type is known for having unisexual flowers.

5. **Identifying the Correct Term**: The term used to describe a spike with unisexual flowers is "catkin".

6. **Characteristics of Catkin**: Catkins are typically cylindrical in shape and consist of clusters of flowers. They often lack petals and are primarily pollinated by wind.

7. **Examples of Plants with Catkins**: Common examples of plants that produce catkins include the cottonwood tree and the oak tree.

**Final Answer**: A spike with unisexual flowers is called a **catkin**.

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