Most life on Earth depends upon plants for energy. Plants capture light from the sun and use it to build up chemical stores of energy. This is called photosynthesis.
The basic structure of a plant cell is shown below. Photosynthesis relies on many structures in the cell all working together, each playing its role.
The diagram below shows the same plant cell, as viewed with the light microscope, and with the transmission electron microscope.
Animal and plant cells have certain structures in common.
|Cytoplasm||Where enzymes and other proteins are made. Location of reactions in anaerobic respiration.|
|Nucleus||Contains DNA which carries the genetic code for making enzymes and other proteins used in chemical reactions such as photosynthesis and respiration.|
|Cell membrane||Allows gases and water to diffuse freely into and out of the cell. Controls the transport of other molecules.|
|Mitochondrion (plural is mitochondria)||Contains enzymes for the reactions in aerobic respiration (in animals, plants and yeast).|
|Ribosome||Where amino acids are joined together to make a protein.|
Plant cells also have additional structures:
|Chloroplast||Contains the green pigment, chlorophyll, which absorbs light for photosynthesis, and the enzymes needed for photosynthesis.|
|Cell wall||Made from cellulose fibres. Strengthens the cell and supports the plant.|
|Vacuole||Filled with cell sap to help support the cell.|
Animal cells may also have vacuoles, but these are small and temporary. In animals, they are commonly used to store or transport substances.