(i) The ground tissue if formed of simple permanent tissues like parenchyma, collenchyma and sclerenchyma.
(ii) Ground tissue system of leaves is called mesophyll. It is made up of two types of photosynthetic cells, i.e., palisade and spongy. Palisade parenchyma contains abundant chloroplasts. Spongy parenchyma occurs towards the lower epidermis and encloses large intercellular spaces.