The document defines a stem and describes its main functions as supporting leaves and branches, transporting water and nutrients, performing photosynthesis, and storing food. It notes stems can be modified for specialized functions. Some examples of stem modifications include tubers, stolons, corms, tendrils, bulbs, and rhizomes.

1. Made By:
Pranav Ahlawat

2.  Before we go any further in this presentation,
let’s define a stem.
 A stem:
 is generally considered to be the central axis of the
plant.
 supports the leaves and flowers of a plant.
 has nodes from which new shoots and sometimes
new roots can arise.
 is usually found above-ground, but can be
modified and found below-ground as well.

3. FUNCTION OF STEMS
 Stems support leaves and
branches.
 Stems transport water and
solutes between roots and
leaves.
 Stems in some plants are
photosynthetic.
 Stems may store materials
necessary for life (e.g., water,
starch, sugar).
 In some plants, stems have
become adapted for specialized
functions.

4. Stems support a display of
leaves.
Stems orient the leaves
toward the light with minimal
overlap among the leaves.
Asclepias - milkweed

7. Cacti - stout fleshy
stems that are
modified for food and
water storage and
photosynthesis.

8.  Tubers -
accumulation of
food at the tips of
underground
stolons
 The "eyes" of a
potato are the nodes
of a starch-ladened
stem

9.  A corm is a
swollen, vertical
stem with a
papery covering.
 Gladiolus and
Crocus are
examples of plants
that form corms.Crocus corms

10.  Bulbs - large buds
with a small stem at
the lower end
surrounded by
numerous fleshy
leaves, adventitious
roots at base
 Examples include
onion, tulip, and lily

11.  Rhizomes -
horizontal stems
that grow below the
ground with
adventitious roots
 Examples of plants
that can produce
rhizomes are irises,
ferns, and grasses.

12.  Other plants, like
ginger, produce
large, thick rhizomes
called pachymorphs.
The pachymorph
rhizome of Ginger

13.  Honey locust
(modified stem)
 Black Locust (modified
leaf stipules)

14. Grape Tendrils

15.  Stolons or runners -
horizontal stem that
grows above the
ground with long
internodes
 Examples of plants
that can produce
stolons are
strawberry and
airplane plants

16. A stem :
 supports leaves and branches.
 transports water and stores food.
 performs photosynthesis.
 performs specialized functions in different conditions.
Stem Modifications:
• Tuber
• Stolon
• Corm
• Tendril
• Bulb
• Rhizome