Plants might look like one complete entity, but they are made up of many different parts. Each part of a plant has a function in helping the plant to grow, survive and spread. Plant parts may look very different from one another, but the thin stem of a grass plant does much the same job as the massive stem of a large tree. All plant parts work together to help reproduce the plant into the next generation.
Roots help to keep the plant firmly settled in the soil, to help absorb water into the plant, and to store food. In some plants, the roots also are used to create more plants in the next season by sending up shoots.
The stem carries water and food throughout the plant and keeps leaves, fruit and flowers above the soil.
The leaves on a plant are in charge of photosynthesis, which is how a plant turns sunlight to energy. Leaves are also responsible for respiration in a plant.
The plant's flowers are the means by which the plant propagates seeds in order to reproduce. Flowers attract pollinating creatures, either insects or other animals, which in turn pollinate the plants and create seeds.
A fruit is a way to protect the seed and to encourage animals and insects to spread seeds and grow more plants. Animals that eat fruit will drop seeds some distance away, thereby spreading the plants a greater distance than merely dropping seeds would produce.
Seeds are the method by which plants reproduce. Whether by naked seeds, like many flowers produce in pods, or by fruiting and having animals carry away the seed, seeds are the way for a plant to recreate itself in the next generation.