ABSTRACT
The internal organization of plant cells is dependent on membranes. In common with other eukaryotic cells, plant cells contain nuclei, concerned with the storage and expression of genetic information, mitochondria, mostly involved in respiration, and peroxisomes, which have diverse roles in plants. Plastids are a defining feature of every plant cell and are specialized for a variety of functions, notably photosynthesis in all green tissues. Electron micrographs of plant cells show that the cell and the organelles within are all defined by membranes Membrane lipids, phospholipids and galactolipids are the major lipids found in plant cells. Indirectly, the vacuole allows plant cells to grow very much larger than animal cells. Plastids have a variety of functions in plant cells, depending on the cell type and tissue. Meristematic cells contain plastids that lack distinctive morphological features. This has led to them being referred to as proplastids, the juvenile progenitors of all plastids seen in mature tissues, with apparent specialized internal structures.
