Transcript Modifications of roots, stems and leaves

Modifications of roots, stems and leaves
Roots:
A. Bulbs and tubers for storage of food
B. Prop roots: Provide additional anchorage
and support for the plant.
Corn
C. For vital functions:
• Haustoria or sucking roots of Cuscuta
Get nutrients from
the host plant
•Respiratory roots or Pneumatophores
Spongy outgrowths
of roots below.
Help gases diffuse
through pores on the
upper end of the roots
• Floating roots – help plant float and also with
respiration.
• Aerial roots - Not parasitic
Help absorb moisture from the air and
make it available to the plant.
2. Stems:
A.Storage of food – Example tubers in potatoes,
Sweet potatoes
B. Bulbs in onions
• Corms in Crocus:
B. For climbing:
C. Asexual reproduction
Stolon
D. Cladodes or cladophylls:
Stem
Store water and help the plant with
photosynthesis
3. Leaves:
• Modified to spines or thorns for protection against
predators and to minimize water loss through
transpiration.
Thick cuticle to store water such as the
Agave plant found in the desert.
•
Pine trees have needle-like leaves to adapt to the
cold climate. Thick waxy epidermis protects from
cold damage. Sunken stomata reduce water loss.
Adhesive disc/Hold fast – use for climbing.
Example – Boston ivy
• Specialized, highly colored leaf below the flower
to lure pollinators. Called a bract.
Example: Poinsettia and dogwood
Floral bracts
Flower
Thorns – Protection – Example Roses, Pyracantha
Tendrils – Used for climbing or to attach to objects.
Example: Virginia creeper, Peas, Grapes
Leaves modified to lure, trap and digest insects.
Examples: Pitcher plant, Venus fly trap, Drosera
Insects provide extra nitrogen to the plants.
http://natgeotv.com/ca/built-for-the-kill/videos/plants_eating_bugs
Succulent leaves – Lithops ‘ Living stones’