Plant Tissue

 A.    Young tissues / meristem

  • • Apical Meristem

Apical meristem is at the root tip and the shoot buds, producing cells for the plant to grow lengthwise. Elongation is also called primary growth, allowing the roots to make fabric in the soil and shoots to improve presentation of sunlight and carbon dioxide.

  • o Growth of Primary Roots

Term growth will be concentrated near the root tip, which is located 3 zone cells with successive stages of primary growth. From the root tip towards the top, there is a zone of cell division, elongation zone and maturation zone.

  • o Growth of Primary Branch

Apical meristem of a shoot is a dome-shaped mass of cells that divide at the end of the terminal bud.

Two lateral meristem function in secondary growth of vascular cambium, which produces secondary xylem (wood) and phloem, and cambium cork.

  • o Secondary Stem Growth

Vascular cambium is a cylinder composed of meristematic cells that form secondary vascular tissues. During secondary growth, the epidermis produced by primary growth will peel, dry, and fall from the stem. The skin will be replaced by new protective tissues produced by the cork cambium,
o Secondary Growth of Roots

Both the lateral meristem, ie the vascular cambium and cork cambium also develops and produces secondary growth in roots. Vascular cambium is formed in the Stele and produce secondary xylem towards the inside and secondary phloem towards the outside. After the Stele diameter grows larger, the cortex and epidermis broken and loose.

  • • Interkalar Meristem

Meristem is located between the primary meristem tissue and adult tissue. Interkalar meristem cell growth causes the stem length more quickly, before the growth rate

  1. B.     Jaringan dewasa
    1. 1.   Basic tissue (parenchymal)

Parenchymal tissue
Parenchymal tissue is called the basic network because many found almost in every part of plants, such as pith, cortex of roots and stems, leaf mesophyll, endosperm of seeds, fruits fleshy, core radius, and also contained as constituent elements of xylem and phloem, both primary and secondary.
• The characteristics of parenchymal tissue
~ Generally, large cells and thin-walled.
~ Cell was alive and contain chloroplasts.
~ Contains a lot of cavities between cells.
~ Contains many vacuoles.
~ Location of meeting tidal cell (rarely).
• Forms of parenchymal tissue
~ Jarinngan palisade parenchyma, has a round shape elongated / oval such as poles or fence rows and in the palisade parenchyma cells have chlorophyll.
~ Network parenchymal sponges, have a space between the cavity is very large and irregular, the sponges contained small amounts of chlorophyll (unlike a palisade).
~ Network star parenchyma (aktinemkim), has a shape like a star because pentagonal dangling.
~ Network parenchymal folds, found in pine and rice, which forms denngan berllipat inward as well as many contain chloroplasts.
• The function of parenchymal tissue
~ Parenchymal assimilation
There on the green parts of the plant. In his cell there in chloroplasts which plays an important role in the process of photosynthesis. On the assimilation parenchyma tissue forms that dominate there are two kinds, namely forms such as pillars, called tissue pillars and form spongy tissue called sponges. On the pine needle-like leaves are reduced, the assimilation parenchyma walls are folded inward folds called the parenchyma.
~ Parenchymal air
Large inter-cell space, round the constituent cells as a means of flotation in the water. For example parenchyma on water hyacinth petiole, the cells formed branched fingers or a star. Tues functioning parenchymal air store called aerenkim.
~ Parenchymal hoarders
Parenchymal cells contain food reserves contained in the pith of the stem, root tuber, bulb, rhizome root (rhizome), or seeds, etc..
~ Parenchymal water
Cells filled with water, to defend itself against drought
~ Parenchymal carrier
There on the carrier network. In this network parenchymal wall can undergo secondary thickening.

  1. 2.   Brace tissue

To strengthen his body, plants require Brace tissue, there are two kinds of brace tissue, namely:

  • Kolenkim

Characteristic of kolenkim:

  1. The cells are alive.
  2. Thin-walled, because the cells retain kolenkim active protoplasts that can eliminate the thickening of the wall when the cell is stimulated to divide.
  3. The walls contain cellulose, pectin, and hemicellulose .
  4. Soft, pliable not have lignin. But in old plants, the cell wall harden and has lignin also turn into sklerenkim.
  5. Thickening wall is not evenly.
  6. There is at the active plant, usually there directly below the epidermis.
  7. Is plastic (clay)

Based on the ways thickening kolenkim cells, known to some type kolenkim:

  1. Angle Kolenkim (angular)

Thickening  extends to the corner of the cell.

  1. Plate / board Kolenkim ( lamellar)

Thickening occurs in the tangential wall, which is part of the wall parallel to the surface of the organ.

  1. Kolenkim tubular  ( lakunar)

Thickening occurs in the cell that limit the space between cells or between two adjacent cells.

  • Sklerenkim

Characteristics of sklerenkim :

  1. The cells are a dead.
  2. Strong and rigid walls because it contains lignin.
  3. There is at the adult plant.
  4. Wall thickness, because the more defensive sklerenkim cell wall and can not be immediately eliminated, although the protoplasts are still there. However, most cells lose the protoplast  sklerenkim as an adult.
  5. Elastic
  6. Thickening wall is evenly.

Kinds of sklerenkim :

  1. Sklereid

Sklereid often called stone cells, because the walls are hard. Size and shape vary. There is a group, or stand alone.In the body of plants, sklereid contained in the carrier file, parenchymal cells, cortical stem, petiole, leaf meat, roots, fruits and seeds.

  1. Serat (serabut)

Most fiber is a long element with the tip of the pointed, narrow lumen and thick secondary wall. Fibers found in the xylem cells or phloem, or is a layer and is associated with the carrier file.

Fiber can be divided into two, namely hard fibers and soft fiber. Hard fiber have the woody walls because of ligneous plants are generally produced by monocots. While soft fiber is not always contain lignin, is flexible and supple, produced by the dicotyledonous plants.

  1. 3.   Protective Tissues

Epidermis tissue
The epidermis is the cell layers that are most out of the primary plant equipment, such as: roots, stems, for modern, flowers, fruits, and seeds. In this case beberpa botanist has been suggested as follows:
• ALLEN, epidermis in the “root” is called as rhizoderma or epiblem;
• SCHMIDT, epidermis in the “trunk” is derived from the outermost cell layer of the apical meristem; at tunica area.
• HANSTEIN, epidermal layers on the trunk that originated from a single cell layer called dermatogen;
• HABERLANDT, the epidermis is derived from primordial epidermis (epidermis or will be known by protoderm), the origin of initial cells separate.

Epidermal cells derived from primary meristem cells. Location of epidermal cells tightly so that no spaces between cells (non-inter-cellular spaces). There are a few protoplasts were attached to the walls of his cell, indicating epidermal cells are still alive. Vakuola which of these are in the middle, fluid-filled cells can also be colored or colorless. Plastids are usually absent in epidermal cells, epidermal cells have leukoplas, tiny. Chloroplasts are usually present in epidermal cells and used as servants in carrying out the process of photosynthesis.
Thickening, thickening of the epidermal cell wall (thickening of the secondary-thickening), consist of cellulose tangible as the lines of (lamella). On the opposite cell wall thickening was not only accompanied by substance kutin cuticle is also located on the cell membrane. Cuticle any artifacts on the cover cells of the stomata. Stomata are holes located in the epidermis of each limited by two “guard cells” (cells cover). Trichomata (hairs) is derived from the epidermis which form, structure, and function varies. Order trichomata distinguish between unicellular and multicelluler. Epidermal layers are divided into uniseriate epidermis and hypodermic.

 Cork Tissue
• Eksodermis
Formed because of the change function of the cell layers below the epidermis is lost or damaged roots. On the inner wall of his cell that contains suberin lamella-lamella.
• Endodermis
Cell layer contained in the root cell walls often bergabus. This layer is sometimes called the cortex (bark) if the inner and outer cylinders if the center
• Skin cork (periderm)
A network becomes a substitute when episermis epidermis is damaged, peeling, suffered death. Periderm divided into 3, namely: Phellogen, phellem, phelloderm.

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