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CHAPTER 8: SUPPORT AND
MOVEMENT
8.2 SUPPORT SYSTEMS IN PLANTS
Plants are classified as Woody Non-woody
Woody plants with a single stem are called trees.
Woody plants that develop branches close to the ground are called shrubs.
Mango Tree
Hibiscus shrubs
Non-woody plants are also known as herbs.
Non-woody plants depend on the water stored in the cells of the stem for support.
When there is not enough water in these cells, the plants wilt.
Adequate Water in Plants
Inadequate Water in Plants
VARIOUS SUPPORT SYSTEMS IN PLANTS BUTTRESS ROOTS (WOODY
PLANTS)The taproot system of large
trees does not provide good support.
Many of these large trees have buttress roots at the base of the stem to provide extra support.
These roots form a very strong base, enabling the trees to grow very tall.
Examples: rain tree, flame of the forest, rubber tree, durian tree
Buttress Root
PROP ROOTS (WOODY PLANTS)The prop roots of the banyan develop from the branches to grow downwards into the ground to give the tree extra support.
Prop roots of maize grow from the nodes of the stem close to the soil surface.
VARIOUS SUPPORT SYSTEMS IN PLANTS
Prop Root
CLASPING ROOTS (NON-WOODY PLANTS)
Clasping roots enable the plant to climb by growing around and clasping its support.
Examples : orchids, money plants, pepper plants
VARIOUS SUPPORT SYSTEMS IN PLANTS
Clasping Root
TENDRILS (NON-WOODY PLANTS)
A tendril = a coiled structure which develops from the stem or leaf.
Tendrils wind themselves around the support and help the plant to climb.
Examples : cucumber, garden pea, pumpkin, long bean, bitter gourd plants
VARIOUS SUPPORT SYSTEMS IN PLANTS
Tendrils
THORNS (NON-WOODY PLANTS)
A thorn = a modified branch and it cannot be easily removed from the stem.
The rose and the bougainvillea plants climb by means of thorns.
VARIOUS SUPPORT SYSTEMS IN PLANTS
Thorns
PRICKLES (NON-WOODY PLANTS)
A prickle = an outgrowth of the epidermis and can be easily removed from the stem.
Example : rose
VARIOUS SUPPORT SYSTEMS IN PLANTS
Prickles
AIR SACSThe brown algae is common on rocky shores.
It is alternately exposed and covered by the tides every day.
This alga has air sacs for support because the air sacs provide buoyancy.
VARIOUS SUPPORT SYSTEMS IN PLANTS
Air Sacs
STILT ROOTSMangrove trees which grow in muddy places have stilt roots that provide additional support.
Stilt roots develop from the main stem of the mangrove trees.
VARIOUS SUPPORT SYSTEMS IN PLANTS
Stilt Root