Roots
- Organ that anchors a vascular plant in the solid, absorbs minerals and water,
and often stores carbohydrates and other reserves.
Functions of roots:
- Anchorage
- Storage of food and materials
- Absorption (update) and conduction (movement) of water and mineral nutrients
to the aboveground parts of the plants
- Growth
- Symbiotic relationship with nitrogen-fixing bacteria
- Production of gibberellins, hormones that stimulate the growth of stems
Taproot System
- Has a large primary root and smaller lateral roots
- Primary roots grow straight downward and become the dominant root of the
plant
- Some are fleshy and store food
- Plants under this group are called dicot plants
Ex. Mango tree, Gumamela, carrots, radishes
Fibrous Root System
- The primary root dies and many slender secondary roots arise from the base of
the stem
- The sizes of the roots are similar
- Plants under this group are called monocot plants
Ex. Grasses, corn, bamboo
,Root Anatomy
Epidermis
- The outer layer of thin-walled, rectangular cells acts as a protective covering
Cortex
- Thin-walled parenchyma cells that function in food storage
Endodermis
- Boundary between cortex and the vascular cylinder
Pericycle
- The first layer of cells within the endodermis
- Starting point of lateral roots
Vascular Tissue - Both monocots and dicots have vascular cylinders that contain xylem
and phloem
- Dicot: Xylem is star-shaped and phloem is found between points in the star
- Monocot - alternating xylem and phloem that surround a pith
Growth Zones of a Rooth
Root cap
- Covers and protects root tip
- Releases CO2 that combines with water forming carbonic acid to corrode rocks
and other coarse particles
Zone of Cell Division
- Contains meristematic cells
- Newly formed cells are added to the root cap below and on the zone of
elongation above
Zone of Elongation
- Cells become longer as they become specialized
, - Responsible for the increase in the length of roots
Zone of Maturation
- Mature and fully differentiated cells
- Easily recognized due to the presence of root hairs
Root Modifications
Buttress Roots
- Aerial roots that look like buttresses give architectural support to the trunks of
trees
- Because of moist conditions in the tropics, root systems are shallow
Prop Roots
- Organ that anchors a vascular plant in the solid, absorbs minerals and water,
and often stores carbohydrates and other reserves.
Functions of roots:
- Anchorage
- Storage of food and materials
- Absorption (update) and conduction (movement) of water and mineral nutrients
to the aboveground parts of the plants
- Growth
- Symbiotic relationship with nitrogen-fixing bacteria
- Production of gibberellins, hormones that stimulate the growth of stems
Taproot System
- Has a large primary root and smaller lateral roots
- Primary roots grow straight downward and become the dominant root of the
plant
- Some are fleshy and store food
- Plants under this group are called dicot plants
Ex. Mango tree, Gumamela, carrots, radishes
Fibrous Root System
- The primary root dies and many slender secondary roots arise from the base of
the stem
- The sizes of the roots are similar
- Plants under this group are called monocot plants
Ex. Grasses, corn, bamboo
,Root Anatomy
Epidermis
- The outer layer of thin-walled, rectangular cells acts as a protective covering
Cortex
- Thin-walled parenchyma cells that function in food storage
Endodermis
- Boundary between cortex and the vascular cylinder
Pericycle
- The first layer of cells within the endodermis
- Starting point of lateral roots
Vascular Tissue - Both monocots and dicots have vascular cylinders that contain xylem
and phloem
- Dicot: Xylem is star-shaped and phloem is found between points in the star
- Monocot - alternating xylem and phloem that surround a pith
Growth Zones of a Rooth
Root cap
- Covers and protects root tip
- Releases CO2 that combines with water forming carbonic acid to corrode rocks
and other coarse particles
Zone of Cell Division
- Contains meristematic cells
- Newly formed cells are added to the root cap below and on the zone of
elongation above
Zone of Elongation
- Cells become longer as they become specialized
, - Responsible for the increase in the length of roots
Zone of Maturation
- Mature and fully differentiated cells
- Easily recognized due to the presence of root hairs
Root Modifications
Buttress Roots
- Aerial roots that look like buttresses give architectural support to the trunks of
trees
- Because of moist conditions in the tropics, root systems are shallow
Prop Roots
