1. Plant Form and Function
ALCOS Objective 4 and 5

2. Objectives Identify the three basic cell types
Describe the histology of roots, stems, leaves and flowers

3. Introduction Major differences between plant and animal cells
Presence of cell wall
Presence of chloroplast and chlorophyll
Presence of large, central vacuole

4. Plant Cells Three basic plant cell types (Figure 23.2)
Parenchyma - food storage and production, contain numerous chloroplast
Collenchyma - strength and support
Sclerenchyma - strength and support, dead at maturity

5. Plant Tissue Four basic plant tissue types Dermal Tissue (Figure 23.4)
Provides covering and protection
Contain a waxy cuticle designed to help prevent water loss
Stomata
Openings in plant leaf that control the exchange of gases
Root-hairs
Extensions of individual cells that help roots absorb water and minerals
Trichomes
Epidermal hairs that help reduce evaporation from plants

6. Plant Tissue Four basic plant tissue types Vascular Tissue
Xylem – transports water and minerals from the roots to the rest of the plant
Phloem – transports sugars and other compounds throughout the plant
Ground Tissue
Found throughout the plant
F(x): photosynthesis, storage and support

7. Plant Tissue Four basic plant tissue types Meristematic Tissue
Meristems
Regions of actively dividing cells
Apical Meristem – increase plant length
Lateral Meristem – increase plant diameter
Vascular Cambium – produces xylem and phloem
Cork Cambium – produces bark

8. Plant Tissue

9. Plant Organs
Root – plant organ that anchors a plant a absorbs water and dissolved minerals
Four basic root types
Taproot – found in carrots
Fibrous – found in grasses
Proproot – found in corn and mangroves
Pneumatophore – found in bald cypress

10. Plant Organs

11. Plant Organs
Stem
above ground portion of the plant that supports the leaves and flowers
Secondary Growth
Increases diameter
Primary Growth
Increases length
Five stem types
Herbaceous – petunia
Woody – trees and shrubs
Corm – gladiolus
Tuber – potato
Rhizome – iris, ferns

12. Plant Organs

13. Plant Organs

14. Plant Organs Leaf Plant organ used for capturing sunlight
Simple Leaf – blade not divided
Compound Leaf – blade divided into leaflets
Leaf arrangement
Whorled, Alternate, Opposite

15. Plant Organs Leaf Leaf composed of Mesophyll Tissue
Photosynthetic plant tissue made of parenchyma cells
Modified leaf types
Spine – reduces water loss, provides protection (Cacti)
Tendril – helps plant climb, cling to surface of materials (Vines)

16. Flower
Flower
Complex structure made of organs involved in fertilization and seed production
All flower share same four basic structures
Petals
Sepals
Stamen
Pistil

17. Flower
Petals
Colorful structures at the top of a flower stem (Peduncle)
Often with perfume or nectar at their base to attract pollinators

18. Flower Sepals Leaf-like, encircle the peduncle below the petals
Provide protective covering for the flower bud
May be colored

19. Flower Stamen Male reproductive structure Anther Filament
Found at the tip of the stamen
Produces pollen
Filament
Stalk that supports the anther

20. Flower Pistil Female reproductive organ Stigma Style Ovary
Receives the pollen
Style
Stalk that connects the stigma to the ovary
Ovary
Contains one or more ovules
Each ovule contains one egg cell

21. Flower Complete Flower Incomplete Flower Photoperiodism Pollination
Contain all four major flower organs
Petal, Sepal, Stamen, Pistil
Incomplete Flower
Lack one or more major flower organs
Photoperiodism
Response of flowering plants to daily daylight- darkness patterns
Pollination
Transfer of pollen from the anther to the stamen
Maybe pollinated by wind, water or animals

22. Flower

23. Flower

24. Flower