Plant cell parenchyma cells, that covers the external surfaces of leaves, stems and roots. Several cell types may be present in the epidermis. Notable among these are the stomatal guard cells that control the rate of gas exchange between the plant and the atmosphere, glandular and clothing hairs or trichomes, and the root hairs of primary roots. In the shoot epidermis of most plants, only the guard cells have chloroplasts. Chloroplasts contain the green pigment chlorophyll which is needed for photosynthesis. The epidermal cells of aerial organs arise from the superficial layer of cells known as the "tunica" (L1 and L2 layers)
Granule (cell biology) clathrin-coated transport vesicle. The process of proteolysis, removes the unwanted parts from the secretory granule resulting in mature granules. Insulin granules mature in three steps: (1) the lumen of the granule undergoes acidification, due to the acidic properties of a secretory granule; (2) proinsulin becomes insulin through the process of proteolysis. The endoproteases PC1/3 and PC2 aid in this transformation from proinsulin to insulin; and (3) the clathrin protein coat is removed. Granules are one of the non-living cell organelle of plant cell(the others-vacuole and nucleoplasm). It serves as small container of starch in plant cell. In photosynthesis, plants use