Flowers can be unisexual, having only male or female parts, or bisexual, having both types of parts. The male parts of a flower make up the stamens. The entire whorl of stamens in the flower is called the androecium.
The sac-like structures at the top of the stamen are the anthers. The anthers house pollen, which contain the male gametophytes that make the sperm. The thread-like stalks that lift the anthers up are called filaments.
The female parts of the flower make up the pistils. The entire whorl of pistils in the flower, which may be separate or fused together, is called the gynoecium.
The sticky tips at the top of the pistils that receive pollen are called stigmas. The swollen bases of the pistils are the ovaries. Inside the ovaries are tiny pearl-like structures called ovules. The ovules contain the female gametophytes, which make the eggs. The slender stalks that connect each stigma to an ovary are called styles.