Collenchyma is the supporting tissue underlying the epidermis of stems and leaf petioles. It consists of cells with thickened walls at the corners. These thickenings contain pectin substances, which give the cell walls strength and elasticity. Thanks to this, collenchyma performs a supporting function, supporting young plant organs. It also provides flexibility to the stems and petioles, allowing them to bend without breaking. The development of collenchyma is associated with plant growth in length. As the stem becomes lignified, the role of collenchyma decreases and it is replaced by sclerenchyma.