Plant Morphology

1
Plant Morphology

• By
• Holly NeeSmith
• Stephanie Gilliam

Provided by Dr. James Corbett, Agriculture
Teacher, Lowndes Co. High School GA Ag Ed
Curriculum Office To accompany Georgia
Agriculture Education Curriculum July
2002 Adapted by Georgia Organics 2009
2
Leaf Structure

• A leaf is held away from its stem by a stem-like
  appendage called a petiole.
• The base of the petiole is attached to the stem
  at a node.
• The blade is the expanded thin structure on
  either side of the midrib and is usually the
  largest, most conspicuous part of a leaf

3
Leaf Parts

• The cuticle is part of the epidermis
• It produces a waxy layer called cutin, which
  protects the leaf from dehydration and disease.
• On the top and bottom is a layer of thick, tough
  cells called the epidermis. Its primary function
  is to protect the other layers of leaf tissue.

4
Leaf Parts Continued

• Special epidermal cells called guard cells open
  and close in response to environmental stimuli,
  such as changes in weather and light.
• They regulate the passage of water, oxygen, and
  carbon dioxide into and out of the leaf through
  tiny openings called stomata.
• Located between the upper and lower epidermis is
  the mesophyll.
• Located within the mesophyll cells are
  chloroplasts, where photosynthesis takes place.

5
Roots

• The roots help to provide support by anchoring
  the plant and absorbing water and nutrients
  needed for growth.
• They can also store sugars and carbohydrates,
  which the plant uses to carry out other
  functions.
• Plants can have either a taproot system (such as
  carrots) or a fibrous root system

6
Stems

• Stems carry water and nutrients taken up by the
  roots to the leaves.
• The food produced by the leaves moves to other
  parts of the plant.
• The cells that do this work are called the xylem
  cells (move water) and phloem cells (move food).
• Stems also provide support for the plant,
  allowing the leaves to reach the sunlight they
  need to produce food.

7
BUDS

• A bud is an undeveloped shoot from which
  embryonic leaves or flower parts arise
• A leaf bud is composed of a short stem with
  embryonic leaves
• A flower bud is composed of a short stem with
  embryonic flower parts.
• Buds are named for the location they inhabit on
  the stem surface.
• Enlarged buds or parts of buds form the edible
  portion of some horticultural crops