Plant structure consists of two basic parts: the shoot and the roots. The shoot consists of the stem, leaves, and flowers. 

• The stem grows towards sunlight.
• The plant uses its leaves to photosynthesize.
• The plant uses its roots to gather water and nutrients from the soil.
• Many plants reproduce via flowers. Flowers produce pollen and seeds.

All flowering plants have a similar structure. The flower contains colorful leaves called sepals and petals, as well as reproductive structures called stamens and pistils.

Sepals protect the bud of the flower, whereas the colorful petals attract pollinators, such as insects or birds.

Pistils contain the flower's ovaries, whereas stamens produce pollen grains. Stamens and pistils are often located in different flowers of the same plant. 

To reproduce, seed plants need to be pollinated. During pollination, the pollen grain produced by the stamens of one flower are transported to the ovaries of another flower's pistil. This results in fertilization, where the nuclei of the pollen cell and the egg cell are united. 

Seed plants can be divided into wind-pollinated and insect-pollinated plants. Wind-pollinated plants often have humble-looking flowers. Their drooping stamens produce light pollen grains that the wind carries to another flower's pistil. Birch is an example of a wind-pollinated plant. 

In contrast, the flowers of insect-pollinated plants are often large, colorful, and scented. These features attract insects to feed on the flower's nectar and to transport pollen from one flower to another at the same time. 

After pollination, the cells of the pollen grain and the egg cell are combined in a process known as fertilization. The fertilized egg cell of the pistil develops into a seed, which in time becomes a new plant in itself.

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Pollination and fertilization.