There are three types of cells that make up the ground tissue in plants. These are:
Parenchyma: This is tissue made up of cells that have thin primary walls and in which the protoplasm is retained. Cells making up parenchyma can take on a large number of roles that are controlled by hormones released in the plant. A few of the many roles played by parenchyma include photosynthesis in leaves, storage of nutrients in the stem, branches, fruit, seed, etc., repair of damage in plants, etc.
Collenchyma: Collenchyma is made up of cells with thick primary walls that continue to retain their protoplasm. This tissue provides strength to plant tissue and supports it structurally.
Sclerenchyma: This is tissue consisting of cells that lose their protoplasm at maturity. The cells have very thick walls and is the primary support tissue in parts of plants that have ceased to elongate