a) Network structure of outer leaves
Leaf morphology consists of :
- Leaf blade ( lamina ) .
- Petiole ( petiolus ) , there is a section which is attached to the rod is called the base of the petiole . There are certain plants whose leaves do not stemmed leaves , such as grass .
- Leaf midrib ( folius ) , at the base of the monocot plants and wide flat leaves and stems wrapped . For example : banana leaf midrib and taro leaf midrib .
Leaves that have three sections called perfect leaf , banana leaf and as taro leaves . Leaves that do not have one or more of the leaf is called the leaf is not perfect , such as mango leaves and guava leaves .
On the leaf surface sheets are bone or leaf veins . Type the veins there are four kinds , namely :
- Pinnate , for example on mango leaves ,
- Menjari , for example, the leaves of papaya ,
- Curved , for example on yam leaf ,
- Parallel , for example in maize leaves ,
Dicotyledonous plants typically have leaves with pinnate leaves and bone structure menjari . While monocot plants have leaves with parallel veins arrangement or curved .
b ) Network Structure in Leaves
1 ) The epidermis Leaves
The epidermis is a single layer of cells whose walls have thickening of the substance cutin ( cuticle ) or sometimes from lignin . In the epidermis there are stomata ( leaf mouth ) flanked by two cover cells . No stomata are located on the top surface , for example in plants whose leaves float ( in lotus leaf ) , there are just under the surface , and some are found on both leaf surfaces ( top and bottom ) . Ficus plants have epidermis that is composed of two layers of cells . Additional tools contained in the leaf epidermis , such as trichomes ( hair ) and the fan cells .
2 ) leaf mesophyll ( basic network )
Mesophyll consists of parenchyma cells are arranged spatially and lots of space between cells . In most dicotyledonous leaves , mesophyll differentiated into palisade parenchyma ( tissue mast ) and spongy parenchyma ( spongy tissue ) . Palisade cells elongated shape , contains many chloroplasts , and arranged a meeting . Irregularly shaped spongy parenchyma , branched , contain fewer chloroplasts , and composed tenuous .
3 ) File Carrier Leaves
Files contained in the carrier leaves the bone that serves as a means of transport and as a reinforcement leaf .
4 ) Additional Network Leaves
Additional network includes specialized cells that normally occur in the leaf mesophyll , such as crystalline cells and glands .
0 komentar:
Post a Comment