1. Flowering Plants Structure and Organization
Chapter 24
BIOL 1000
Dr. Mohamad H. Termos

2. Biology, 9th ed, Sylvia Mader
Chapter 25
Non-vascular
Structure and Organization of Plants

3. Biology, 9th ed, Sylvia Mader
Chapter 25
Vascular
Structure and Organization of Plants

4. Organs of Flowering Plants
Biology, 9th ed, Sylvia Mader
Chapter 25
Organs of Flowering Plants
Flowering plants share many common structural features.
A typical plant features three vegetative organs
roots, stems, and leaves
Flowers, seeds, and fruits are structures involved in reproduction.
Structure and Organization of Plants

5. Organs of Flowering Plants
Biology, 9th ed, Sylvia Mader
Chapter 25
Organs of Flowering Plants
Roots: Generally, the root system is at least equivalent in size and extent to the shoot system. Functions: Anchors, absorbs, produces hormones, stores minerals.
Stems: Shoot system of a plant is composed of the stem, branches, and leaves. Main axis of a plant that elongates and produces leaves. Can be herbaceous or woody
Leaves: major part of the plant that carries on photosynthesis
Structure and Organization of Plants

6. Biology, 9th ed, Sylvia Mader
Chapter 25
Plant cell review
What things make plant cells unique?
-cell wall
-chloroplasts
-large vacuoles
Structure and Organization of Plants

7. Tissues of Flowering Plants
Biology, 9th ed, Sylvia Mader
Chapter 25
Tissues of Flowering Plants
Meristematic tissue enables growth
Apical meristems - at the tips of stems and roots
Apical meristem produces:
Epidermal tissue
Ground tissue
Vascular tissue
Structure and Organization of Plants

8. Tissues of Flowering Plants: Epidermal Tissue
Biology, 9th ed, Sylvia Mader
Chapter 25
Tissues of Flowering Plants: Epidermal Tissue
Forms the outer protective covering of a plant
Epidermis contains closely packed epidermal cells
Cuticle – waxy covering of epidermal cells 8
Structure and Organization of Plants

9. Biology, 9th ed, Sylvia Mader
Chapter 25
Epidermal Tissue
Root Hairs
Trichomes
Stomata 9
Structure and Organization of Plants

10. Biology, 9th ed, Sylvia Mader
Chapter 25
Epidermal Tissue
In older woody plants, the epidermis of the stem is replaced by periderm
Major component is cork
New cork is made by cork cambium 10
Structure and Organization of Plants

11. Tissues of Flowering Plants: Ground Tissue
Biology, 9th ed, Sylvia Mader
Chapter 25
Tissues of Flowering Plants: Ground Tissue
Ground tissue forms bulk of a flowering plant
Photosynthesis
Storage
Support
Structure and Organization of Plants

12. Tissues of Flowering Plants: Vascular Tissue
Biology, 9th ed, Sylvia Mader
Chapter 25
Tissues of Flowering Plants: Vascular Tissue
Xylem - transports water and minerals from the roots to the leaves
Phloem transports sucrose and other organic compounds from the leaves to the roots
Structure and Organization of Plants

13. Flowering Plants are Either Monocots or Eudicots
Biology, 9th ed, Sylvia Mader
Chapter 25
Flowering Plants are Either Monocots or Eudicots
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Seed
Root
Stem
Leaf
Flower
Monocots
Root xylem and
phloem in a ring
Vascular bundles
scattered in stem
Leaf veins form
a parallel pattern
Flower parts in threes
and multiples of three
One cotyledon in seed
Cotyledon (Kataleeden): an embryonic leaf in seed-bearing plants, one or more of which are the first leaves to appear from a germinating seed.
Eudicots
Root phloem between
arms of xylem
Vascular bundles
in a distinct ring
Leaf veins form
a net pattern
Flower parts in fours or
fives and their multiples
Two cotyledons in seed
Structure and Organization of Plants

14. Organization and Diversity of Roots
Biology, 9th ed, Sylvia Mader
Chapter 25
Organization and Diversity of Roots
Root cap contains root apical meristem
Zone of cell division - contains primary meristems
Zone of elongation - cells that are lengthening and becoming specialized
Zone of maturation - fully differentiated cells
Structure and Organization of Plants

15. Organization and Diversity of Roots
Biology, 9th ed, Sylvia Mader
Chapter 25
Organization and Diversity of Roots
Primary root (taproot) - Fleshy, long single root, that grows straight down. Stores food
Fibrous root system - Slender roots and lateral branches. Anchors plant to soil
Adventitious roots - Roots develop from organs of the shoot system
Structure and Organization of Plants

16. Shoot tip and Primary Meristems
Biology, 9th ed, Sylvia Mader
Chapter 25
Shoot tip and Primary Meristems
Structure and Organization of Plants

17. Organization and Diversity of Stems
Biology, 9th ed, Sylvia Mader
Chapter 25
Organization and Diversity of Stems
Herbaceous Stems: Mature non-woody stems exhibit only primary growth. Outermost tissue covered with waxy cuticle. Stems have distinctive vascular bundles (Herbaceous eudicots: Vascular bundles arranged in distinct ring, Monocots: Vascular bundles scattered throughout stem)
Woody Stems: Primary tissues formed each year from primary meristems; increase length. Secondary tissues develop during first and subsequent years from lateral meristems; increase width.
Bark: contains cork, cork cambium, and phloem
Wood: Secondary xylem that builds up year after year. Annual ring is made up of spring wood and summer wood. In older trees, inner annual rings, called heartwood, no longer function in water transport
Structure and Organization of Plants

18. Biology, 9th ed, Sylvia Mader
Tree Trunk
Chapter 25
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
annual rings
heart wood
sap wood
vascular
cambium
phloem
cork
a. Tree trunk,
cross-sectional view
b. Tree trunk,
longitudinal view
a: © Ardea London Limited
Structure and Organization of Plants

19. Organization and Diversity of Leaves
Biology, 9th ed, Sylvia Mader
Chapter 25
Organization and Diversity of Leaves
Leaves contain:
Upper and lower epidermis: 1- Waxy cuticle, 2- Trichomes, 3- Stomata
Mesophyll: 1- Palisade mesophyll containing elongated cells, 2- Spongy mesophyll containing irregular cells with air spaces
Contains many chloroplasts 19
Structure and Organization of Plants

20. Biology, 9th ed, Sylvia Mader
Chapter 25
What do plants need to survive?
sunlight
water and minerals
Carbon dioxide
Leaves- Broad and thin to absorb more solar energy
Stomata – open to allow gas exchange
Roots:
Water- enters through osmosis
Minerals- absorbed and concentrated through active transport
Stems/Leaves: Water transported from roots by:
Root pressure
Cohesion – water molecules “cling” together
Roots  stems  leaves  out of stomata
Minerals – moved with the water and absorbed by cells that need them
Photosynthesis: Produces organic nutrients for energy- sugars. Sugars need to be transported to plant parts that need the energy
Sugar moves into phloem by active transport. Water follows due to osmosis 
Creates positive pressure of water that carries sugars to other plant parts  then sugar removed actively  Water leaves phloem due to osmosis  xylem
Structure and Organization of Plants