Botany-Plant Anatomy

1. Plant Anatomy
Plant Anatomy
Study of tissue and cell structure of plants.
(In zoology, anatomy is study of internal
organs; histology is study of tissues/cells.)

2. Cell Theory
All of life is composed of 1 or more cells.
Cells arise only from pre-existing cells, via
cell division or cell fusion.
Cells are units of metabolic processes.
Each cell contains set of hereditary
information (DNA), transferred from cell to
cell, coding for structural & functional
features.

3. contains DNA
storage: pigments,
acids, ergastic
substances
respiration
protein synthesis
& transport of
materials
transport &
modification
photosynthesis
cell recognition,
transport
structural support
ribosomes: site of
protein
synthesis
storage high
energy carbs.

4. Ergastic Substances:
not actively metabolized (storage/waste)
chromoplasts
amyloplasts (starch grains):
alpha-1,4-glucopyranoside
crystals (Ca-oxalate; silica)
druses raphides styloids prismatics
aleurone grains: protein oil bodies

5. cell wall
mainly cellulose:
beta-1,4-glucopyranoside

6. lignin - secondary cell wall
function?

7. meristem - region of actively dividing cells
1) apical (shoot & root);
2) lateral (vascular & cork cambia)
Cell differentiation:
1) Cell expansion (elongation)
2) Cell maturation / specialization

8. Plant Tissues & Cell Types
Tissue:
= group of cells with common function or structure.
Three broad tissue types:
1) Dermal - outside layer(s)
2) Vascular - conduction
3) Ground - between dermal and vascular
Simple vs. Complex Tissue:
1 versus 2 or more cell types

9. Ground Tissue
Parenchyma: Gen. metabol.
1) Isodiametric to elongate
2) Primary cell wall
3) Living
Collenchyma: support
1) Elongate
2) Primary cell wall thick,
uneven, rich in pectins
3) Living

10. Ground Tissue
Sclerenchyma
1) Secondary cell wall (+ primary)
2) Dead at maturity (usually)
Fibers
Elongate, sharply tapering

11. Ground Tissue
Sclerenchyma
1) Secondary cell wall (+ primary)
2) Dead at maturity (usually)
Sclereids
Isodiametric to irregular

12. Vascular Tissue
Xylem
Water & mineral conduction
Tracheary elements + parenchyma + sclerenchyma
Phloem
Sugar conduction
Sieve members + parenchyma + sclerenchyma
- Both complex tissues

13. Tracheary Elements
Tracheids - Imperforate Vessels - Perforate
Angiosperms (most)
Gnetales
A few Monilophytes

14. Sieve Elements
Sieve cells - No sieve plates Sieve tube members - Sieve plates
Apomorphy of Angiosperms

15. Dermal & Secretory tissues & cells
Epidermis Glands
Laticifers
Nectaries
Stomates

16. Dermal tissues: Trichome anatomy
Epidermis

17. root cap
root apical
meristem
ROOT (l.s.)
1) Protective root cap
2) Absorptive root hairs

18. ROOT (c.s.)
3) Give rise to new roots endogenously
(from within)

19. Casparian Strip
Function: forces fluids
from outside
through plasma
membrane =
selective absorption

20. SPOROPHYTIC
SHOOT

21. Stems:
• Give rise to leaves exogenously
• Do not have a protective “cap” of cells
• Do not have root hairs (but may have trichomes)

22. Stelar types
eustele atactostele

23. Protoxylem maturation

24. Vascular cambium - a lateral meristem

27. Conifers: non-porous

28. Ring porous Diffuse porous

29. Wood Ray Anatomy

30. Leaf anatomy

31. Stomata

32. C3
Photosynthesis

33. Kranz anatomy

34. C4 Photosynthesis

35. CAM photosynthesis