Guard cells differ from other epidermal cells in having:
Chloroplasts
Guard cell and epidermal cell are two types of cells found in the epidermis of plants. The epidermis is originated from the dermal tissue of plants, bringing the contact of the plant with the external environment. It is the outer layer of leaves, stems, and roots of the plant. Guard cells contain chloroplasts and are capable of carrying out photosynthesis. But epidermal cells do not contain chloroplasts.