Planteceller

Planteceller are the basic structural and functional units of plants. They are eukaryotic cells that often perform photosynthesis and form the tissues and organs of terrestrial and aquatic plants.

A defining feature is the cell wall made primarily of cellulose, which provides rigidity. The wall surrounds a plasma membrane and encloses a large central vacuole. Planteceller contain chloroplasts for photosynthesis, and they communicate with neighboring cells through plasmodesmata, cytoplasmic channels crossing cell walls.

Inside, they house a nucleus, mitochondria, and an extensive endomembrane system (endoplasmic reticulum and Golgi apparatus). Chloroplasts contain chlorophyll, thylakoid membranes, and stroma, enabling light energy to be converted into chemical energy. Other plastids, such as leucoplasts and chromoplasts, store starch or pigments. The chloroplasts and mitochondria have their own DNA and ribosomes, reflecting an endosymbiotic origin.

Metabolism and growth are characterized by turgor-driven expansion and vacuole control of cell size. Most plant cells store energy as starch rather than glycogen. During cell division, a cell plate forms at the center to create a separating cell wall. Plant tissues include ground, dermal, and vascular tissues formed by specialized cell types such as parenchyma, collenchyma, and sclerenchyma.

In leaves, stomata opened by guard cells regulate gas exchange, while plasmodesmata facilitate transport and communication between neighboring cells.