Unisexual flowers
Unisexual flowers are flowers that contain either pistil or stamen, but not both. The term "unisexual" refers to the fact that these flowers have only one sex organ. These flowers are also known as imperfect flowers because they lack either the male or female reproductive organs.

Types of Unisexual Flowers
Unisexual flowers can be further classified into two categories: male flowers and female flowers.

Male Flowers:
Male flowers are flowers that contain only stamens. The stamen is the male reproductive organ of a flower and consists of the filament and the anther. The anther produces pollen grains, which contain the male gametes. Male flowers are typically smaller and less showy than female flowers and are often found in clusters.

Female Flowers:
Female flowers are flowers that contain only a pistil. The pistil is the female reproductive organ of a flower and consists of the stigma, style, and ovary. The stigma is the receptive surface for pollen grains, the style connects the stigma to the ovary, and the ovary contains the ovules, which develop into seeds after fertilization. Female flowers are usually larger and more conspicuous than male flowers.

Examples of Unisexual Flowers
Some common examples of unisexual flowers include:

- Corn: Corn plants have separate male flowers (tassels) and female flowers (ears) on the same plant. The tassels contain the stamens, while the ears contain the pistils.
- Watermelon: Watermelon plants also have separate male and female flowers. The male flowers have stamens, while the female flowers have pistils.
- Cucumbers: Cucumber plants have separate male and female flowers. The male flowers contain stamens, while the female flowers have pistils.

Importance of Unisexual Flowers
Unisexual flowers play a crucial role in plant reproduction. Since they have separate male and female flowers, they require a pollinator to transfer pollen from the male flowers to the female flowers. This ensures that fertilization occurs and seeds are produced. The presence of separate male and female flowers also allows for cross-pollination, which promotes genetic diversity among plant populations.

In conclusion, the flower that contains either a pistil or stamen is called a unisexual flower. These flowers have either male or female reproductive organs, but not both. They are important for plant reproduction and can be found in various plant species such as corn, watermelon, and cucumbers.

A) Unisexual flowers