Anatomy of Flowering Plants

NCERT Line-by-Line Breakdown for NEET 2026

Unit 2: Structural Organisation in Plants and Animals

While Morphology studies the external form, Anatomy studies the internal structure. In this chapter, we dissect the plant to understand Tissues (Meristematic & Permanent) and the internal organization of Roots, Stems, and Leaves.

1. The Tissues

A tissue is a group of cells having a common origin and usually performing a common function.

A. Meristematic Tissues (Active Division)

1. Apical Meristem
Occurs at tips of roots and shoots. Produces primary tissues (Primary growth).
Note: Axillary bud is formed by cells ‘left behind’ from shoot apical meristem.

2. Intercalary Meristem
Occurs between mature tissues (e.g., Grasses). Regenerates parts removed by grazing herbivores.

3. Lateral Meristem
Occurs in mature regions. Responsible for Secondary Growth (Girth).
Example: Fascicular vascular cambium, Cork cambium.

B. Permanent Tissues (Lost ability to divide)

I. Simple Permanent Tissues (One type of cells)

Tissue	Cell Wall & Nature	Function & Location
Parenchyma	Thin, Cellulosic. Living. Isodiametric.	Photosynthesis, Storage, Secretion. Major component of organs.
Collenchyma	Thickened at corners (Cellulose, Hemicellulose, Pectin). Living.	Mechanical support to young stems/petiole. No intercellular spaces.
Sclerenchyma	Thick, Lignified. Dead at maturity.	Mechanical support. Includes Fibers & Sclereids (Grittiness in Guava/Pear).

II. Complex Permanent Tissues (Multiple types of cells)

[Image of xylem and phloem elements]

Xylem: Conducts water/minerals. Elements: Tracheids, Vessels (Characteristic of Angiosperms), Xylem Fibers, Xylem Parenchyma (Living).
Phloem: Transports food. Elements: Sieve tube elements, Companion cells, Phloem Parenchyma, Phloem Fibers (Bast fibers – Jute/Flax).

⚠️ NEET Fact: Gymnosperms lack vessels in Xylem and Companion cells in Phloem (they have Albuminous cells).

2. The Tissue Systems

Epidermal	Epidermis, Stomata, Trichomes (Stem hairs – multicellular), Root hairs (Unicellular).
Ground	All tissues except epidermal and vascular. Cortex, Pericycle, Pith, Mesophyll (in leaves).
Vascular	Xylem + Phloem (Vascular Bundles).

Types of Vascular Bundles

Radial: Xylem and Phloem on different radii (Roots).
Conjoint: Xylem and Phloem on same radius (Stem/Leaves).
- Open: Cambium present (Dicot Stem).
- Closed: Cambium absent (Monocot Stem).

3. Anatomy: Dicot vs Monocot

This is the most critical section for diagram-based questions.

A. Root

Dicot Root

Cortex: Parenchymatous.
Endodermis: Casparian strips (Suberin).
Pericycle: Origin of lateral roots & vascular cambium.
Pith: Small or inconspicuous.
Vascular: Diarch to Hexarch (2-6 bundles).

Monocot Root

Similar to Dicot but…
Pith: Large and well developed.
Vascular: Polyarch (More than 6 bundles).
No secondary growth.

B. Stem

[Image of dicot vs monocot stem anatomy]

Feature	Dicot Stem	Monocot Stem
Hypodermis	Collenchymatous	Sclerenchymatous
Vascular Bundles	Arranged in a Ring (Ring porous). Conjoint, Open.	Scattered. Conjoint, Closed.
Unique Feature	Endodermis rich in starch (Starch Sheath).	Water-containing cavities (Lysigenous cavities) in vascular bundles.

C. Leaf

Dicot (Dorsiventral): Stomata more on lower surface. Mesophyll differentiated into Palisade (upper) and Spongy (lower).
Monocot (Isobilateral): Stomata equal on both sides. Mesophyll undifferentiated. Presence of Bulliform Cells (in Grasses) to minimize water loss by curling.

📝 Rapid Fire MCQs

Q1. Casparian strips occur in:

A) Epidermis
B) Pericycle
C) Cortex
D) Endodermis

Click to check Answer

Answer: D) Endodermis (Made of waxy material Suberin).

Q2. Vascular bundles in monocot stems are:

A) Scattered and Open
B) Scattered and Closed
C) Ringed and Open
D) Ringed and Closed