DENDROLOGY

Detailed explanation-1: -Since the mesophyll tissue is the major photosynthetic tissue in roses a large majority of the chloroplasts are found here, both in the palisade cells and mesophyll cells (Figure 4). However, the palisade cells usually contain more chloroplasts than the spongy cells.

Detailed explanation-2: -Cells of the palisade parenchyma contain three to five times as many chloroplasts as those of the spongy parenchyma.

Detailed explanation-3: -The cells in the spongy mesophyll layer are not as closely packed as the cells in the palisade mesophyll layer. This creates air spaces inside the leaf to enable gases to move in and out. There are not as many chloroplasts in the spongy mesophyll cells as there are in the palisade mesophyll cells .

Detailed explanation-4: -Palisade mesophyll layer: Tightly packed layer of elongated cells located directly below the upper epidermis. These cells contain most of the chloroplasts in a leaf.