0 votes
in Internal Structure of Root, Stem and Leaf by (47.6k points)
closed by

Explain the internal structure of Dicot root with the help of well-labelled diagram and also differentiate between vascular bundle od Monocot and dicot root?

1 Answer

+1 vote
by (48.2k points)
selected by
Best answer

1. Epiblema:

  • ( = piliferous layer = rhizodermis)
  •  It is the outermost layer.
  • Consists of thin walled, living parenchymatous cells.
  • The outer walls of the cells of epiblema form unicellular tubular prolongations called root hairs.
  • These hairs help in absorption of water from the soil.

2. Cortex:

  • It is situated below the epiblema upto endodermis.
  • It is made up of thin walled circular or polygonal living parenchymatous cells with numerous intercellular spaces.
  • Cortical cells store starch.

3. Endodermis:

  • The innermost layer of cortex that surrounds the stele is called endodermis.
  • Cells of endodermis have special thickenings called casparian strips in their radial and tangential walls.
  • Endodermal cells outside the protoxylem, do not have casparian strips.
  • Such cells are called passage cells.

4. Pericycle :

  • This unilayered structure is found inside the endodermis.
  • Consists of thin waded cells.

5. Vascular bundles:

  • These are always arranged in a ring and are radial i. e., Xylem and phloem are situated at different radii.
  • The protoxylem is always away from the centre and metaxylem towards the centre.
  • This condition of xylem is called exarch.
  • The vascular bundles in gram root are tetraeh.

6. Conjuctive tissue:

  • In between the xylem and phloem patches of paren-chymatous cells are found called as conjunctive tissue.

7. Pith:

  • It is found in the centre and is feebly developed.
  • It is made up of parenchymatous cells with intercellular spaces.

Welcome to Sarthaks eConnect: A unique platform where students can interact with teachers/experts/students to get solutions to their queries. Students (upto class 10+2) preparing for All Government Exams, CBSE Board Exam, ICSE Board Exam, State Board Exam, JEE (Mains+Advance) and NEET can ask questions from any subject and get quick answers by subject teachers/ experts/mentors/students.