The cell is the basic unit of structure of living organisms
The systems are composed of the organs, the organs are composed of the tissues, and the tissues are composed of the cells, The cell is the building unit of the living organism’s body, and it is the unit of structure in the living organisms.
The animal cell
The animal cell is the building unit of the animal body, The body of the animals or the humans is made up of a group of systems (as the digestive system, the respiratory system, the circulatory system, ……..) that work integrally to keep the living organisms alive.
The systems consist of a set of organs (as the stomach, two lungs, the heart, ………), Each organ consists of a group of the similar or different tissues, Each tissue consists of a group of symmetric units called the cells.
The plant cell
The plant cell is the building unit of the plant body, and the plant body also is made up of systems (the shoot system and the root system).
These systems are made up of organs as the roots, the stems and the leaves, Each organ in the plant is made up of tissues, and each tissue is made up of similar units called the cells.