E2 Stem modifications

Modified stems adapt plants to what?

different factors in the environment

Below ground modifications:

• Rhizomes

• Corms

• Stolons

• Tuber

• Bulbs

Rhizomes

• fleshy, creeping underground stems

• short internodes and small, scale-like leaves

  • ginger

Corms

short, thickened stem, usually covered with papery leaves

Stolons

slender stems that grow horizontally

Tuber

enlarged tip of a stolon that stores starch

Bulbs

Large buds surrounded by numerous fleshy leaves with a small stem at the lower end

• stores food

• onions, lilies, hyacinths, tulips

Stem above ground modifications:

• cladophylls

• thorn

• spine

• prickles

• tendril

Cladophylls

flattened, leaf like stems

• greenbriers, some orchids, and prickly pear cactus

Thorn

modified stem/branches

• sharp, pointed woody structures that arise from the axillary buds

Spine

modified leaves

• cacti have both thorns and spines

Prickles

epidermal outgrowths of the bark

Tendril

slender, sensitive structures of many climbing plants that support the plant

• modified stems, leaves, or leaf parts or roots