Welcome brothers still meet again with me. This time I will review the plant life that has balance in the life of this world. Plants are living organisms are composed of some of the principal organs.
1. The root is a very important plant organs. In addition to absorbing water and nutrients, will serve to anchor the plant body in his place. Even some that serves to store food reserves.
In seed plants closed between monocot plant root structure with the root structure of dicotyledonous plants have differences, as follows:
a. Plants Monocots (dashed one):
- Root root fibers are arranged in the system.
- Kaliptra protected root tip and the boundary between the tip of the root kaliptra obvious.
- Kaliptra has a growing point called kaliptragen.
- Do not have the cambium.
- Having endodermis and persikel (fairy cambium).
- Branching on endogenous ie root branching from within.
b. Dikotil plants (two-layered).
- The roots are arranged in a taproot system.
- The boundary between the root tip kaliptra unclear.
- Has the cambium, endodermis and parisikel.
- Not memunyai kaliptrogen (forming kaliptra).
- Branching endogenous roots.
In the transverse container monocot or dicot roots generally have parts from the outside to the inside is as follows:
a. Epidermal cells are compact, thin cell walls, making it easy to penetrate the water. Epidermal cells can form root hairs that function expands the absorption field.
b. Cortex is composed of several layers of thin-walled cells. In the cortex there is plenty of space between cells. This serves to ventilate the room. The innermost layer of the cortex is a barrier between the cortex with a central cylinder is called endothermic.
c. Endodermis endodermis cell shape and arrangement different from the shape and composition of the surrounding cells, the cell walls of the endodermis which is perpendicular to the central cylinder coated cork substance (suberin). So that water and substances drawn therein can not pass through the wall.
At the root of the cross section, thickening agents cork it looked as midpoints endodermis cell wall that is located radially. The points were named point Kapsari. So with the thickening agent that cork, endodermis cell wall that is perpendicular to the cylinder center impassable water and substances dissolved in it in force to penetrate the endodermis cell plasma.
Plasma cells are semi-permeable, allowing water entry and endodermis regulate substances that are dissolved in it before entering the central cylinder. Cross-sectional diagram that shows how to root water uptake and mineral.
d. Central cylinder / stele deepest part of the root is the central cylinder / stele. The outermost layer is called the center of the cylinder parisikel / perikambium. Cells were dealing with file perikambium xylem located to the right or the left can be meristem tissue to form a branch of the root, so the formation of endogenous root branch.
Next to the parisikel are radial-type transport vessels. In dicotyledonous plants, between the xylem and phloem cambium which there is a growing point of the secondary. Cambium divides to form the bark outwards and inwards forming wooden vessels.
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