Glossary:
1
2
3
4
tissue
dermal tissue
ground tissue
vascular tissue
 Tissues – groups of cells that are similar in appearance and function, for
example:
 Structures (organs) – groups of tissues working together with a common
function; e.g., roots, stems, leaves, flowers, fruits, and seeds.
 Plant – made up of a number of coordinated structures to form a working unit.
Plant Tissue Systems
The tissues of a plant are organized into three tissue systems: the dermal
tissue system, the ground tissue system, and the vascular tissue system.
Use information from the table to answer the questions below it.
Tissue System Component Location of Tissue Systems
and Its
Tissues
Functions
Dermal Tissue Epidermis
Periderm (in
System
• protection
older stems
• prevention of and roots)
water loss
Parenchyma
Ground
Tissue System tissue
•
Collenchyma
photosynthesis tissue
• food storage Sclerenchyma
• regeneration tissue
• support
• protection
Xylem tissue
Vascular
Tissue System Phloem tissue
• transport of
water and
minerals
• transport of
food
Plant Tissues
Tissues are groups of cells with similar structures & functions







Plants have 3 tissue systems --- ground, dermal, and vascular
tissues
Plant tissues make up the main organs of a plant --- root, stem,
leaf, & flower
Ground tissue makes up most of the plant's body, dermal tissue
covers the outside of the plant, & vascular tissue conducts water
& nutrients
Plant cells are arranged into tissues and tissue systems
A simple tissue is composed of only one type of cell; a complex
tissue is composed of more than one cell type.
Plants are composed of specialized cells and tissues
In plants, the formation of new cells, tissues and organs is
restricted almost entirely to regions known as meristems
Dermal Tissue:



Covers the plant body and consists of epidermis in young plants &
non-woody plants that is replaced later by periderm in woody
plant
Epidermis is made of parenchyma cells in a single layer
Epidermis on stem and leaves prevents water loss by
transpiration & produces a waxy material called cuticle
Epidermis Of a Leaf




Epidermal cells on roots form extensions called root hairs to
absorb H20 & nutrients
Openings in the epidermis on the underside of a leaf where gases
are exchanged are called stomata (stoma, singular)
Sausage-shaped guard cells are found on each side of the stoma
to help open and close the pore to prevent water loss
Dead cork cells replace epidermis in woody stems & roots
Ground Tissue:


Ground tissue constitutes the majority of the plant body and
contains parenchyma, collenchyma, and sclerenchyma cells
Ground tissue of the leaf (called mesophyll) uses the energy in
sunlight to synthesize sugars in a process known as
photosynthesis

Spongy Mesophyll of Leaf


Ground tissue of the stem (called pith and cortex) develops
support cells to hold the young plant upright
Ground tissue of the root (also called cortex) often stores
energy- rich carbohydrates
Vascular Tissue:



Vascular tissues transport water and dissolved substances inside
the plant and helps support the stem
The 2 types of vascular tissue are xylem & phloem
Xylem carries water and dissolved ions from the roots to stems
and leaves


Phloem carries dissolved sugars from the leaves to all other parts
of the plant
Xylem has 2 kinds of conducting cells --- tracheids & vessel
elements
Xylem Cells




Tracheids are long, narrow sclerenchyma cells with walls and pits
for water to move between them
Vessel elements are short, wide sclerenchyma cells without end
walls stacked on top of each other
Angiosperms (flowering plants) have tracheids & vessel elements,
while gymnosperms (cone bearers) only have tracheids
Phloem moves sap (dissolved sugars & minerals) from source
(where they are made) to sink (where they will be used)
Phloem Cells



Phloem is made of cells called sieve tube members and companion
cells
sieve tube members are stacked to form tubes called sieve tubes
with porous sieve plates between the cells for movement of
sugars
Companion cells are along each sieve tube member & help in
loading sugar into the sieve tube
CONCLUSION:



Seed plants contain 2 types of vascular tissue (xylem & phloem)
to help transport water, minerals, & food throughout the root &
shoot systems
Plant cells have several specialized structures including a central
vacuole for storage, plastids for storage of pigments, and a thick
cell wall of cellulose
Plant cells are all box-shaped in appearance