The theory was put forward by Schuepp It is similar to the tunica-corpus theory of the shoot apex. It is based on differences in the planes of cell division. The theory says that the cells in the root apex divide in a pattern called T-divisions. The outer region of the root apex is the Kappe.
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The theory was put forward by Schuepp It is similar to the tunica-corpus theory of the shoot apex. It is based on differences in the planes of cell division. The theory says that the cells in the root apex divide in a pattern called T-divisions. The outer region of the root apex is the Kappe. The cells of this region divide first horizontally.
The lower daughter cell then divides longitudinally, i. Thus the planes of the two divisions form a T in a median longitudinal section of the root. The inner region of the apex is the korper. In this region the T is inverted, i. This type of division has been found among the members of Gramineae and Fagaceae. In this type, three groups of initials are found at the apex — outer dermatogen , middle periblem , and inner plerome.
In this type there is a single row of initials which, ultimately, gives rise to various zones of the root including the root cap. In this type, generally two rows of initials are observed at the apex. One of the layers gives rise to the stele and the other to the cortex and root cap.
In certain members of the families Juglandaceae, Rosaceae, Leguminosae, Tiliaceae etc. The epidermis arises from the outermost layer of the cortex. The first type is found in Zephyranthes sp. The second type is very rare and found in Allium sativum, Aloe vera, Amaryllis, Eucharis etc. The third type is found in Haemanthus coccineus. Differences between the shoot apex and the root apex: 1.
In contrast to that of the shoot apex, the apical meristem of the root apex generates cells not only toward the axis but also away from it to form the root cap. The apical meristem of the root is sub- terminal in position as the root cap remains terminal. The root apex forms no branches, and no lateral structures like the leaves.
For that reason the root apex shows no change in morphology. The root apex grows uniformly as it never produces nodes and internodes. The root branches arise endogenously beyond the region of most active growth. Related Articles:.
The theories are: 1. Apical Cell Theory 2. Histogen Theory 3. Korper-Kappe Theory. Apical Cell Theory: This theory was proposed by Nageli who drew the attention to the occurrence of a single apical cell or apical initial that composes the root meristem. A single apical cell is present only in vascular cryptogams, e.
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Megasporogenesis and Megagametogenesis in Plants Embryology Biology. It divides longitudinally and the two daughter cells thus formed have the potentiality of cell division. In this region the T is inverted, i. The body-cap concept and tunica-corpus concept both are based solely on the planes theeory cell division. It is based on differences in the planes of cell division. The root apex forms no branches, and no lateral structures like the leaves.
The Korper-Kappe Theory of Root Apex | Essay | Botany