Parts of the Root
Root hair
Root hairs are outgrowths of epidermal cells.
Adaptations of the Root hair cell to their function
- It has a long root hair/that is elongated to increase the surface area for absorption of water and mineral salts.
- Have thin cell walls to reduce the distance through which water and mineral salts will be absorbed.
- It has dense cytoplasm with numerous mitochondria to produce more energy for active transport.
- Lack a cuticle making them permeable to water and mineral salts.
- Flexible and can bend penetrating through the soil particles.
Epidermis
Bears root hairs that increases surface area for absorption of water and dissolved mineral salts.
Cortex
It is made of thin-walled parenchyma cells that form packaging or storage tissues.
Endodermis
This is the innermost layer of the cortex that surrounds the vascular bundles.
It controls the materials entering the vascular bundles.
Pericycle
It is a single layer of cells immediately below the endodermis.
It is meristematic and gives rise to lateral roots.
Vascular bundles
Comprise of xylem and phloem tissues.
In monocot roots, the vascular bundles alternate in a ring around the pith.
Dicot roots have a central star-shaped xylem with phloem found between the radiating arms of the xylem.
Functions of the Roots
- Absorption of water and dissolved mineral salts.
- Anchorage
Other functions
- Storage of food.
- Gaseous exchange
