Modifications of roots stems and leaves Roots A

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’