Internal structure of root Questions in English

(D) The Casparian strip and passage cells are characteristic features of the endodermis in roots.
In the provided image:
- $(A)$ represents a Dicot root.
- $(B)$ represents a Monocot root.
- $(C)$ represents a Dicot stem.
- $(D)$ represents a Monocot stem.
Both Casparian strips (suberin deposits) and passage cells (thin-walled cells) are found in the endodermis of roots (both Dicot and Monocot). Therefore,they are observed in both $(A)$ and $(B)$.

(A) In monocot roots like maize,the number of xylem bundles is usually more than six,which is typically referred to as polyarch condition.
In contrast,dicot roots generally exhibit diarch,triarch,or tetrarch conditions.
Therefore,based on the number of xylem bundles,the maize root is termed as polyarch.

(B) In the primary internal structure of a dicotyledonous root,the stele consists of the pericycle,vascular bundles,and conjunctive tissue (parenchyma between xylem and phloem).
In the primary internal structure of a dicotyledonous stem,the stele consists of the pericycle,vascular bundles,and pith.
Conjunctive tissue is a characteristic feature of the root stele and is absent in the stem.
Therefore,conjunctive tissue is a stelar tissue in the dicot root but not in the dicot stem.

(D) In dicotyledonous roots,the lateral roots originate from the $Pericycle$ cells.
These cells are located just inside the $Endodermis$.
When the plant needs to develop lateral roots,the cells of the $Pericycle$ undergo rapid cell division (meristematic activity) to form a root primordium.
This primordium then pushes through the $Endodermis$,$Cortex$,and $Epidermis$ to emerge as a lateral root.
Therefore,the origin of lateral roots is endogenous.

(C) In the provided diagram of a root hair cell:
$1$. The label $X$ points to the dense, spherical organelle located within the cell, which is the $Nucleus$.
$2$. The label $Y$ points to the outer boundary of the adjacent cell, which is the $Cell wall$.
Therefore, $X$ represents the $Nucleus$ and $Y$ represents the $Cell wall$.

(C) The endodermis is the innermost layer of the cortex in roots.
It is characterized by the presence of Casparian strips on its radial and tangential walls.
These strips are composed of a water-impermeable,waxy substance called $suberin$.
$Suberin$ prevents the movement of water and dissolved solutes through the cell walls,forcing them to pass through the plasma membrane into the cytoplasm,which allows the plant to regulate the uptake of water and minerals.

(B) The correct answer is $B$.
In the anatomy of a dicotyledonous root,the parenchymatous cells that are located between the xylem and phloem vascular bundles are specifically referred to as conjunctive tissue.
These cells play a role in the storage of food and can sometimes become meristematic during secondary growth.

(B) The correct answer is $B$.
Suberin is a hydrophobic,waxy substance that provides protection and prevents water loss.
It is characteristically deposited in the cell walls of the $phellem$ (cork) cells in the stem,which are part of the periderm.
Additionally,it is deposited in the radial and tangential walls of the $endodermis$ of the root,forming the Casparian strips,which regulate the movement of water and solutes into the vascular cylinder.

(B) . Conjunctive tissue is the parenchymatous tissue present between the xylem and phloem bundles in roots $(III)$.
$B$. Casparian strips are the water-impermeable bands of suberin found in the endodermal cells $(IV)$.
$C$. Subsidiary cells are specialized epidermal cells that surround the guard cells of the stomata $(I)$.
$D$. Starch sheath refers to the endodermis of the stem,which is rich in starch grains $(II)$.
Therefore,the correct matching is $A-III, B-IV, C-I, D-II$.