what is Root System its Types, regions and root modification | study science

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                                                 Root System

 Root system - the underground part of plant is called root system.There are three types of roots i.e taproot, fibrous root and adventitious root

                                                                     

                                                      3 Types of Root

             

                        1.Taproot                        2. Fibrous Root                       3.  Adventitious Root

 

1.Taproot

 

• Taproot is the primary & the main root that develops from the radicle.
• It bears lateral roots of several order that are called secondary or tertiary roots
• Tap root is usually found in dicot (2 Cotyledons) plant
  
• Eg: Mustard, Carrot

 

2.Fibrous root

• In fibrous root, the primary root is short lived.
• Primary root is replaced by large number of roots originate from base of stem
• Fibrous root is the main root system of monocot plant
  
• Eg: Wheat plant, Maize

 

3.Adventitious root

• Adventitious root are roots that develop from any part of plant except radicle.
• They may be aerial or underground.
• Adventitious root may grow from node, tree branch, stem base stem cutting 
• Eg: Banyan tree, Rose.

 

                                    Regions of the Root

 

 Root is divided into four different region

1. Root Cap

• Root cap is a thimble like structure which covered the root
• Root cap protect the tender apex of the roots as it makes its way through the soil.
• When root cap wears out it is constantly renewed
• In aquatic plant, root cap is like loose thimble (root pocket)

 

2. Region of meristematic cells 

• It is a small region of actively dividing cells
• The cells of this region are very small, thin walled & dense cytoplasm.

3. Region of elongation

• The region of elongation lies next to the meristematic region.
• The cells elongate & enlarge to make the root grow in length

4. Region of maturation

• Region of maturation lies next to the region of elongation
• The cells mature & differentiate into various tissues
• Some epidermal cells form very fine & delicate, thread like structures called root hairs
• Root hairs absorb water & minerals from the soil
  

 

                        Modifications of root

In some plants, roots change their shape and structure and become modified to perform functions other than absorption & conduction of water and minerals.

Root are modified for storage of food, support and respiration. 

1. Tap root of carrot, turnips & Adventitious root of sweet potato, get swollen and and store food.

2. Hanging structures that support a banyan tree are called prop roots

supporting roots coming out of the lower nodes of the stem of maize & sugarcane are called stilt roots.

 

3. Many roots come out of the ground & grow vertically upwards are called pneumatophores which help to get oxygen for respiration.

Eg: Rhizophora.

Functions of Root System.

1. Root help in absorption of water & minerals from the soil
   
2. Root provide a proper anchorage to plant parts
   
3. Transport Water & minerals to the plant
   
4. Storing reserve food material
   
5. Synthesis of plant growth regulator