The leaf is commonly two types.
- Dorsiventral leaf
- Isobilateral leaf
The Dorsiventral leaf commonly found in dicotyledons plant and grow in horizontal direction with upper and lower surface.
The isobilateral leaf found in monocotyledon plants.
Anatomy of dicotyledons leaf:-
The internal structure of dicotyledons leaf is as follow-
Anatomy of dicotyledons leaf
The leaf is covered on both surface by single layered epidermis. The outer wall of epidermis is covered by thick cuticle which is helpful for water does not pass through them and transpiration from surface of epidermis reduced and only small amount of water evaporated by transpiration. The epidermis also prevent the entrance of pathogens into the interior of leaf. It also protect soft internal tissue of leaf from mechanical engineering. Several small opening are found in the epidermal layer of leaf called stomata. These stomata mostly found in lower epidermis and very less amount present upon upper epidermis. In floating leaf the stomata found only on upper epidermis part in some merged leaf the stomata are absent in xerophytic leaf the stomata are sanken type found in depression. Each stomata is surrounded by two guard cells. The guard cells are living and contain chloroplast which regulate opening and closing of stomata. The guard cells surrounded by accessory cells and are found in scattered condition. The stomata are meet form exchange of gases between leaf and atmosphere.
The tissue of leaf lies between upper and lower epidermis called mesophyll tissue. Commonly the cell of mesophyll are two types.
Palisade parenchyma
Spongy parenchyma
The Palisade parenchyma present near upper epidermis the cells are elongated and cylindrical present in two or three layer. The inter cellular space absent between them the cell contain chloroplast which receive sunlight as function of photosynthesis. The lower portion of mesophyll near the lower epidermis in leaf is called spongy parenchyma the cells are loose irregular thin wall and inter cellular space present among them the cells contain chlorophyll and carry on photosynthesis presence of inter cellular space which adoptable two exchange of gases between cells and mesophere. The air space that surrounded the spongy parenchyma near the stomata directly connected with them. The chloroplast are more dense in Palisade parenchyma then spongy parenchyma.
The vascular bundle specially present in middle of leaf and surrounding by parenchyma with small amount of chloroplast. The vascular bundles is surroundings by bundle sheath. In vascular bundle the xylem and phloem present which help to translocate the water and other material to different part of the leaf.
Anatomy of dicotyledons leaf
Epidermis
The leaf is covered on both surface by single layered epidermis. The outer wall of epidermis is covered by thick cuticle which is helpful for water does not pass through them and transpiration from surface of epidermis reduced and only small amount of water evaporated by transpiration. The epidermis also prevent the entrance of pathogens into the interior of leaf. It also protect soft internal tissue of leaf from mechanical engineering. Several small opening are found in the epidermal layer of leaf called stomata. These stomata mostly found in lower epidermis and very less amount present upon upper epidermis. In floating leaf the stomata found only on upper epidermis part in some merged leaf the stomata are absent in xerophytic leaf the stomata are sanken type found in depression. Each stomata is surrounded by two guard cells. The guard cells are living and contain chloroplast which regulate opening and closing of stomata. The guard cells surrounded by accessory cells and are found in scattered condition. The stomata are meet form exchange of gases between leaf and atmosphere.
Mesophyll tissue
The tissue of leaf lies between upper and lower epidermis called mesophyll tissue. Commonly the cell of mesophyll are two types.
Palisade parenchyma
Spongy parenchyma
The Palisade parenchyma present near upper epidermis the cells are elongated and cylindrical present in two or three layer. The inter cellular space absent between them the cell contain chloroplast which receive sunlight as function of photosynthesis. The lower portion of mesophyll near the lower epidermis in leaf is called spongy parenchyma the cells are loose irregular thin wall and inter cellular space present among them the cells contain chlorophyll and carry on photosynthesis presence of inter cellular space which adoptable two exchange of gases between cells and mesophere. The air space that surrounded the spongy parenchyma near the stomata directly connected with them. The chloroplast are more dense in Palisade parenchyma then spongy parenchyma.
Vascular bundle
The vascular bundle specially present in middle of leaf and surrounding by parenchyma with small amount of chloroplast. The vascular bundles is surroundings by bundle sheath. In vascular bundle the xylem and phloem present which help to translocate the water and other material to different part of the leaf.
