In the given list how many plants have unisexual flowers on the same plant. Cucurbits, Papaya, Castor, Coconut, Date palm, Maize.

Options

A. one
B. four
C. three
D. two

Answer

To determine how many plants from the given list have unisexual flowers on the same plant, we need to analyze each plant type based on their reproductive structures.

### Step-by-Step Solution:

1. **Understanding Flower Types**:
- Flowers can be classified as perfect (bisexual) or unisexual (either male or female).
- Unisexual flowers can be either staminate (male) or pistillate (female).

2. **Identifying Monoecious and Dioecious Plants**:
- **Monoecious plants** have both male and female unisexual flowers on the same plant.
- **Dioecious plants** have male and female flowers on separate plants.

3. **Analyzing Each Plant**:
- **Cucurbits**: These plants (like cucumbers and pumpkins) have both male and female flowers on the same plant. Therefore, they are monoecious.
- **Papaya**: This plant has separate male and female plants, making it dioecious.
- **Castor**: Castor plants have both male and female flowers on the same plant, hence they are monoecious.
- **Coconut**: Coconut palms also have both male and female flowers on the same plant, making them monoecious.
- **Date Palm**: This plant has separate male and female plants, so it is dioecious.
- **Maize**: Maize plants have both male (tassels) and female (ears) flowers on the same plant, thus they are monoecious.

4. **Counting Monoecious Plants**:
- From the analysis, the monoecious plants are:
- Cucurbits
- Castor
- Coconut
- Maize
- The dioecious plants are:
- Papaya
- Date Palm

5. **Final Count**:
- Therefore, there are **4 plants** in the list that have unisexual flowers on the same plant.

### Conclusion:
The answer is **4** plants have unisexual flowers on the same plant.

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