The mesophyll tissue is composed of palisade cells and spongy cells in dicot leaves. The palisade cells are found below the upper epidermis and they are columnar cells without inter cellular spaces. All the cells are rich in chloroplast pigment. Whereas the number of chloroplast present in lesser in spongy tissue. The spongy cells are polygonal in shape and are arranged loosely with lesser number of chloroplast.
The mesophyll tissue is not differentiated into palisade cells and spongy cells in monocot leaves. They are formed of compactly arranged isodiametric cells. Presence of bundle sheath which extends from the vascular bundle to upper and lower epidermis. The Bundle sheath is the characteristic feature of monocot leaves.