Animals and plants are made of cells. Cells form the basic "building blocks" for living things.
Cells are very small. They are the basic building blocks of all animals and plants. This photograph shows cells seen through a microscope:
Animal cells usually have an irregular shape, and plant cells usually have a regular shape.
Cells are made up of different parts. It is easier to explain what these parts are by using diagrams like the ones below:
CELL MEMBRANE: Controls what substances can get into and out of the cell.
CYTOPLASM: Jelly-like substance that fills-up the entire cell. The other components of the cell float in the cytoplasm. Plants cells have a thin line of cytoplasm.
MITOCHONDRIA: This is where the cell gets its energy. In the human body, food we have digested reacts with oxygen in the mitochondria to make energy for the cell.
NUCLEUS: The nucleus controls what happens inside the cell. It carries genetic information to instruct the rest of the cell what to do next.
VACUOLES: Contain a liquid called sap, which keeps the cell firm.
CHLOROPLASTS: They are organelles found in plant cells that specialize in converting sunlight into energy that plants can use. This process is called photosynthesis.
CELL WALL: Made up by cellulose, which supports the cell.
Do you want to know more? Watch this video: