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Root apex

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gohil sanjay bhagvanji

This document summarizes theories of root apex organization. It defines the root apex as the region where primary tissues are derived and composed of apical meristem cells. Two historical theories are described: 1) The Apical Cell Theory proposed a single apical cell governs growth but was later replaced. 2) The Korper-Kappe Theory proposed cells divide in two planes, with one zone resembling an inverted T and the other a straight T, similar to the tunica-corpus model of shoot apices. However, this theory also fails to fully explain differences between species.

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ROOT APEX Presented by :- Patel Vanita L. Roll NO :- 210 CBO :- 405 M.SC sem :- 2 Department of life sciences , H.N.G.U.,Patan
CONTENT • Definition of root apex • Theories of root apex :  Apical cell theory Korper-kappe theory
Definition  Root Apex :- • All primary tissues of the plant body are derived either from root apical meristem . This may show variation in their organisation .
Root apex
• during the later stages of development of embryo the cells at the root pole become arranged in a pattern characteristic of the species . • This group of cells comprises the apical meristem of the primary root .
Root apex organization • Several theories have been proposed to describe the root apex organization . 1. Apical cell Theory 2. Histogen Theory 3. Korper-Kappe Theory
Apical cell theory • This theory was put forth by nageli in 1858 solitary apical cells occur in many of algae , bryophytes and vascular cryptogams . • The discovery of the apical cell in cryptogams led to the concept that such cells exits in seed plants as well .
• The apical cell was interpreted as a constant structural and functional unit of apical meristems governing the whole process of growth . • The apical cell theory was superseded by the histogen theory .
Root apex
Korper – Kappe Theory • Schuepp proposed that the cells at the root apex divide in two planes. • The zone with inverted T type of division was referred to as cap . • Where as other with straight ‘T’ As body .the theory basically recalls the tunica corpus concept of shoot apex and simillarly it also fails to explain the differences in behaviour in different species .
Root apex
Reference • A Text book of botany Plant anatomy and economic botany volume -3 : by – S. N. Pandey A. Chadha WWW.Biologydiscussion.com
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Root apex

  • 1. ROOT APEX Presented by :- Patel Vanita L. Roll NO :- 210 CBO :- 405 M.SC sem :- 2 Department of life sciences , H.N.G.U.,Patan
  • 2. CONTENT • Definition of root apex • Theories of root apex :  Apical cell theory Korper-kappe theory
  • 3. Definition  Root Apex :- • All primary tissues of the plant body are derived either from root apical meristem . This may show variation in their organisation .
  • 5. • during the later stages of development of embryo the cells at the root pole become arranged in a pattern characteristic of the species . • This group of cells comprises the apical meristem of the primary root .
  • 6. Root apex organization • Several theories have been proposed to describe the root apex organization . 1. Apical cell Theory 2. Histogen Theory 3. Korper-Kappe Theory
  • 7. Apical cell theory • This theory was put forth by nageli in 1858 solitary apical cells occur in many of algae , bryophytes and vascular cryptogams . • The discovery of the apical cell in cryptogams led to the concept that such cells exits in seed plants as well .
  • 8. • The apical cell was interpreted as a constant structural and functional unit of apical meristems governing the whole process of growth . • The apical cell theory was superseded by the histogen theory .
  • 10. Korper – Kappe Theory • Schuepp proposed that the cells at the root apex divide in two planes. • The zone with inverted T type of division was referred to as cap . • Where as other with straight ‘T’ As body .the theory basically recalls the tunica corpus concept of shoot apex and simillarly it also fails to explain the differences in behaviour in different species .
  • 12. Reference • A Text book of botany Plant anatomy and economic botany volume -3 : by – S. N. Pandey A. Chadha WWW.Biologydiscussion.com