1. Plant Cells and Tissues

2. I. General Information A. Three main plant cell types 1. Parenchyma
2. Collenchyma
3. Sclerenchyma

3. 1. Parenchyma Can differentiate into all cell types
Living cell, can still divide
F(x)s =
Plant growth
Food production (photosynthesis)
Food storage (e.g. potatoes)
Wound healing & regeneration

4. 2. Collenchyma a. Living cells b. Have thicker walls than parenchyma
c. Can form long rope-like fibers
(e.g. linen)
d. Can stretch (occur in elongation zones)
e. F(x) = strength, support, elongation

5. 3. Sclerenchyma Usually dead while functioning
Thick secondary wall, no stretch
F(x) = strength, support
2 types:
i. fibers
ii. Sclereids
(seed coats,
nut shells
& fruit)

6. I. General Information B. Three main types of plant tissue
1. Ground tissue
2. Dermal Tissue
3. Vascular Tissue

7. C. Ground tissue 1. Surrounded by dermal tissue
2. All tissue that is NOT dermal tissue or vascular tissue

8. C. Ground tissue 3. Contains all three types of cells
(mostly parenchyma)
4. Make up most of non-woody
roots, stems & leaves

9. C. Ground tissue
5. Many f(x)s
Photosynthesis
Food storage
Support

10. C. Ground tissue

11. D. Dermal Tissue 1. General Forms the “skin”
(outside covering) of a plant
b. Covers roots, stems & leaves
c. F(x) depends on
location

12. D. Dermal Tissue Epidermis Cuticle Root Hairs Stomata Cork
d. Examples:
Epidermis
Cuticle
Root Hairs
Stomata
Cork

13. D. Dermal Tissue 2. Epidermis a. Parenchyma b. Usually ONE cell thick
c. Outer protective
covering of young
& mature woody plants

14. D. Dermal Tissue Waxy layer secreted by epidermis prevent dehydration
3. Cuticle
Waxy layer secreted by
epidermis
b. F(x) =
prevent dehydration

15. D. Dermal Tissue 4. Root Hairs Modification of epidermis
b. F(x) =Absorption
of water from soil

16. D. Dermal Tissue a. Location = stems & leaves
5. Stomata
a. Location = stems &
leaves
b. F(x) = osmoregulation & regulation of
gas exchange

17. D. Dermal Tissue c. Composition: two guard cells stoma (opening)

18. D. Dermal Tissue cork 6. Cork (bark) (Dead cells) F(x) =
i. Replace epidermis in woody stems & roots
ii. Protect
plant

19. E. Vascular Tissue F(x)s a. Transports water & nutrients
b. Supports the plant

20. E. Vascular Tissue
2. Two kinds of vascular tissue
a. Xylem
b. Phloem

21. E. Vascular Tissue F(x) = Conducts Water & Nutrients UP from roots
3. Xylem
F(x) =
Conducts
Water & Nutrients UP
from roots
(X elevator only goes up)

22. 3. Xylem b. Two kinds of conducting cells
i. Tracheids
long, thick-walled scelerenchyma
Thin separations
between them

23. i. Tracheids Water moves between them through PITS (thin porous
areas of
cell wall)

24. 3. Xylem Short, wide sclerenchyma No end walls
ii. Vessel Elements (members)
Short, wide sclerenchyma
No end walls
No separations btwn. them
(arranged end to end)
Not found in Gymnosperms

25. Tracheids vs Vessel Elements

26. 4. Phloem F(x) = conducts the Products of Photosynthesis
in every direction
(P elevator moves in every direction)

27. 4. Phloem b. Two kinds of conducting cells 1. Sieve Tube Member
a. F(x) = Conduct sap
b. Stacked to form long
SieveTubes

28. 4. Phloem 2. Companion Cells a. Parenchyma
b. F(x) = Control movement of
sap through sieve tubes