Plants are organized into two sections:

1)  Shoots – stem and leaves

2)  Roots

Stems:

  • Support leaves
  • Transport water and minerals to leaves
  • Transport sugar to the leaves

Two main types of stems

1) Herbaceous – green and soft

  • Contain vascular bundles

o  Collections of xylem (water) and phloem  (carbs)

§  Can be scattered (monocots)

§  Arranged in a ring called vascular cambium (dicots)

Examples:

2) Woody – tough hard tissue

  • Complex

o  Vascular cambium

Annual rings – addition of new xylem for trunk growth

  • Sapwood-young xylem and
  • Heartwood-old xylem filled with oils and resins
  • Bark-protective outer tissue

o  Phloem and cork (outer dead layer that prevents water loss)

3)  Specialized Stems:

  • Rhizomes:  thick fleshy stems that can store water or food.
  • Tubers: underground stems
  • Bulbs:  underground stems

Examples:  Cacti, irises, potatoes and tulips

Leaves:

  • Make sugars for the plant
  • Provide food and oxygen for organisms

Structure:

To maximize sun exposure leaves come in many forms.  The two main types are:

1) Simple Leaves

  • Contain a single blade

2) Compound Leaves

  • Divide into smaller leaflets

Let’s get to the “root” of things:

3 Functions:

  • Anchoring
  • Absorption
  • Transport

Two main types:

1)  Taproots:  long thick root

  • As the plant grows some branching forms called secondary roots

Examples:  dandelions, carrots

2)  Fibrous roots-many main roots and thousands of secondary/tertiary roots

  • Extend laterally

Examples:  orchids, wheat

Monocots and Dicots:

The two divisions of Angiosperms

1)  Monocotyledoneae “Monocots”

2)  Dicotyledoneae  “Dicots”

  • All angiosperm seeds have at least one seed leaf, or cotyledon.
  • Monocots have only ONE seed leaf
  • Dicots have TWO seed leaves that store nutrients for the developing embryo

Include the following headings:

  • Vascular bundles
  • Seed leaves
  • Flower parts
  • Mature leaves
  • Roots

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