presentation 03 - plant tissues
DESCRIPTION
TRANSCRIPT
TissuesTissuesan integrated group of cells with a
common structure and function
Plant TissuesPlant Tissues1. Meristematic tissue: rapid cell division,
lengthening of shoots and roots
2. Dermal tissue: covering for the plant body
3. Ground tissue: support, photosynthesis, and storage
4. Vascular tissue: conduction of water, food, and dissolved minerals; strengthens and supports the plant
Meristematic TissueMeristematic Tissue cells that do not
differentiate cells retain the ability to
divide Types:
Apical – primary growth at root and shoot tips
Lateral – secondary growth in trees and shrubs
Intercalary – secondary growth in monocot stems
Apical meristemApical meristem In shoot tips and
root tips Allium cepa root tip
Root cap
Apical meristem
Region of cell differentiation/maturation
Region of cell elongation
Region of cell division
Dermal TissuesDermal Tissues Single layer of cells called the
epidermis in herbaceous plants Guard cells Trichomes Root hairs
Functions Absorption Secretion of cuticle Protection Control of gas exchange
Epidermis
Cuticle
The Ground The Ground Tissue SystemTissue System
Parenchyma cellsParenchyma cells spherical-shaped cells found throughout plant thin primary walls living, metabolizing tissue functions:
Photosynthesis & respiration Storage (starch, oil droplets,
water, and salts) Wound healing & regeneration
CollenchymaCollenchyma beneath the epidermis in
young stems and in large veins of leaves
elongated cells that have unevenly thickened cell walls
alive at maturity flexible support system found uniformly throughout
the plant
SclerenchymaSclerenchyma structural support two types:
fibers – support in wood, bark, leaves, stems
sclereids – protection in fruits, seeds, other plant organs
primary and secondary cell walls.
dead at functional maturity
The Vascular The Vascular Tissue SystemTissue System
Complex Complex Vascular Vascular TissuesTissues
Xylem Conducts water and dissolved
minerals from the roots
Phloem Conducts dissolved food
materials, carbohydrates, in solution
Continuous throughout plant
Support plant body
All 4 types of tissues are present
in the root tip
Young dicot stem Young monocot stem