EXPLANATION: Epidermal cells and cork cells are two types of cells in the outermost layer of the cells. Epidermal cells are arranged in a single layer to cover the whole plant body during primary growth. Cork cells are produced by the cork cambium during secondary growth of plants. Both epidermal cells and cork cells contain water-repellent substances to prevent the water loss from the plant body. The main difference between epidermal and cork cells are the occurrence of each type of cells in the plant body.