Insulin. Insulin is a hormone made by the beta cells in the pancreas. It is the key that opens the doors of cells and allows glucose to get into the cell. Each cell needs glucose to function. Carbohydrates in food are broken down into glucose which enters the blood stream.
The pericycle is a cylinder of parenchyma or sclerenchyma cells that lies just inside the endodermis and is the outer most part of the stele of plants.
In higher plants, peroxisomes contain also a complex battery of antioxidative enzymes such as superoxide. dismutase, the components of the ascorbate-glutathione cycle, and the NADP-dehydrogenases of the pentose-phosphate pathway.