Monocot Root Cross-Section

The primary structure of monocot root consists of the following parts:

Epiblema

• This is the outermost layer of the monocot root. Single-layered, thin-walled parenchymatous cells, colorless, polygonal without intercellular spaces.
• Presence of unicellular root hairs that help in absorption of water and minerals, hence also called piliferous layer or rhizodermis.
• Cuticle, protective coating seen on stems and leaves, is absent
• Stomata are also absent

Cortex

• Cortex might be heterogeneous with outer dead exodermis.
• It forms the largest cell region consisting of multiple layers.
• The cortex cells are made of parenchymatous cells, which helps in storing food and water because of their thin walls and large intercellular spaces.

Endodermis

• It has barrel-shaped parenchyma without intercellular spaces.
• Casparian strip, made of suberin and lignin, is present in young endodermal cells.
• Group of cells called passage cells that conduct fluids are present
• Endodermis help in regulating the movement of water, ions and hormones in vascular system

Stele

The stele of monocot root consists of primary vascular tissues, pericycle, and its associated ground tissues (i.e.pith).

Pericycle

• Pericycle in monocot root consists of single-layered sclerenchymatous cells and parenchyma cells.
• Present just below endodermis
• Pericycle gives lateral roots only
• secondary growth is absent

Vascular Tissues

• Vascular tissue is made up of alternate strands of xylem and phloem
• Vascular bundles are radial
• Xylem is an exarch (protoxylem towards the outside; metaxylem in middle)
• More than 6 vascular bundles are present hence called “polyarch”
• Metaxylem elements are oval or circular

Pith

• Thin-walled parenchymatous cells present
• May or may not have intercellular gaps between each cells
• Pith is large or rarely reduced

Plants that have seeds containing only one cotyledon are known as monocot plants. The root of monocot plants is called monocotyledon root or monocot root. It is a fibrous root with a wide network of thin roots originating from the stem.

The monocot root has more than 8 vascular bundles and this is described as polyarch. It has a large developed pith. Monocot root examples are peas, beans, peanuts, and maize. In this article, we will read about monocot root cross-sections, diagrams, and characteristics of monocot roots.