Answer:
Living things are made up of tiny structural units called cells. Extremely simple living things (called single-cell organisms) may contain only one cell, while complex living things, such as human beings, contain trillions. There are some important differences between plant and animal cells. Plant cells contain cell walls, which keep them firmly in place, while animal cells do not. Some animal cells have protrusions called cilia, which help them move around. Plant and animal cells contain different organelles, which are tiny structures inside the cells that perform different functions. However, both plant and animal cells serve the same basic functions. They divide over time so that plants and animals can change and grow. They also allow plants and animals to absorb nutrients and convert those nutrients into energy.