Plant anatomy is the study of the internal structures of plant organs. The three main plant structures are roots, stems, and leaves. Roots absorb water and nutrients and anchor the plant. Stems provide structure and transport nutrients. Leaves are the main photosynthetic organs and sites of gas exchange. Internally, plant organs contain tissues including epidermis, ground tissues, and vascular bundles. The epidermis protects the plant while vascular bundles transport water and nutrients. Ground tissues provide structure and store nutrients. Roots, stems, and leaves show variations between monocots and dicots in their structures.

1. THE PLANT BODY AND ITS
DEVELOPMENT

2. • What is plant anatomy?
• Plant anatomy is the study of the internal cell
structure and tissues of plant organs.
OR
• Plant anatomy or phytotomy is the general
term for the study of the internal structure of
plants.

3. FUNDAMENTAL PARTS OF PLANT
BODY
• Seed plants have three main structures
• Roots
• Stems
• Leaves
• Linked together by various means.

5. Functions of Roots
• Absorb/Transport water and
nutrients.
• Anchor plant to the ground.
• Hold soil in place and prevent
erosion.
• Storage of sugars made in photosynthesis.

6. • Functions of Stem:
• Support for the plant body.
• Carries nutrients throughout plant

7. Functions of Leaves:
• Main photosynthetic systems.
• Site of gas exchange.

9. INTERNAL ORGANIZATION OF PLANT
BODY
LEAVES
• Cuticle : Extracellular hydrophobic layer that
covers the epidermis leaf.It is made up of lipid
and hydrocarbon polymers integrated with
wax. It is formed by the epidermal cells
providing protection against desiccation and
external environmental stresses.

10. • Epidermis: Outer most layer of leaf.
The two primary functions of the
epidermis on the leaf are to limit
water loss and to control gas
exchange. It is on both sides
- Upper epidermis
- Lower epidermis

11. • Mesophyll: Mesophyll is the internal
ground tissue located between the
two epidermal cell layers of the leaf
and is of two types. -
-Spongy mesophyll:
-Palisade mesophyll:

12. • Function: The most important role of
the mesophyll cells is in
photosynthesis. Mesophyll cells are
large spaces within the leaf that allow
carbon dioxide to move freely.

13. • Guard cells (stomata): Guard cells are cells
surrounding each stoma. They help to regulate
the rate of transpiration by opening and closing
the stomata.

14. • Vascular Bundles: Xylem and phloem tissues
are found in groups called vascular bundles .
• Bundle-sheath cells :are the photosynthetic
cells arranged into a tightly packed sheath
around the vein of a leaf. It forms a protective
covering on leaf vein, and consist of one or
more cell layers,

15. Leaf Internal structure

16. No Basis of
comparison
Monocot Leaf Dicot Leaf
1 Shape The leaf is slender and
long in shape.
The leaf is broader in shape
and relatively small.
2 Leaf
Orientation
The orientation of the
leaf can be described as
isobilateral.
The orientation of the leaf
can be described as
dorsiventral.
3 Upper & Lower
Surface Color
The upper and lower
surfaces of the leaf are
equally green.
The upper surface of the leaf
is dark green while the
lower surface is light green
in color.

17. No Basis of comparison Monocot Leaf Dicot Leaf
4 Venation Pattern The venation pattern
of a monocot leaf is
parallel. Parallel
venation is whereby
the secondary veins
run parallel to each
other off a central,
perpendicular
primary vein.
The venation
pattern in a dicot
leaf is reticulate.
Reticulate
venation is
whereby vein are
interconnected and
form a web-like
network.
5 Epidermal Cells The epidermal cells
have almost straight
lateral walls.
The epidermal
cells have curved
lateral walls.

18. No Basis of comparison Monocot Leaf Dicot Leaf
6 Guard Cells The guard cells of
stomata are dumb-
bell shaped in
monocot leaf.
The guard cells of
stomata are kidney-
shaped in dicot leaf.
7 Vascular Bundles Both small and
large vascular
bundles are
present in
monocot leaf.
The vascular bundles
in dicot leaf are
generally large.
8 Stomata Presence The leaf is
amphistomatic in
nature.
The leaf can be
described as
hypostomatic.

19. No Basis of comparison Monocot Leaf Dicot Leaf
9 Stomata
Arrangement
The stomata are
arranged in
parallel rows and
are uniformly
present on both
surface of the leaf.
The stomata are
arranged randomly
on the epidermis of
dicot leaf.
10 Vascular Bundle
Differentiation
Large vascular
bundles may show
differentiation into
Protoxylem and
meta-xylem
elements.
Large vascular
bundles do not show
differentiation into
Protoxylem
elements.

20. No Basis of comparison Monocot Leaf Dicot Leaf
11 Vascular Bundle
Differentiation
Large vascular
bundles may show
differentiation into
Protoxylem and
meta-xylem
elements.
Large vascular
bundles do not show
differentiation into
Protoxylem
elements.
12 Intercellular
Spaces
The intercellular
spaces are
relatively small
due to compact
arrangement of
mesophyll cells.
The intercellular
spaces are relatively
large due to presence
of loosely packed
mesophyll cells.

21. Monocot Leaf

22. Dicot Leaf

23. Stem: The part of the plant that
is usually above ground and
bears the leaves, reproductive
parts and buds.

24. STEM:
There are three types of tissue systems:
1-Dermal Tissue
2-Ground Tissue
3-Vascular Tissue

27. 1- Dermal Tissue: is composed of
epidermis and periderm.
• Epidermis: is a thin cell layer that
covers and protects underlying cells.
• Periderm: The periderm, also called
bark, replaces the epidermis in plants
that undergo secondary growth.

28. • The outer periderm, or bark, is a
thick layer of nonliving cork cells.
Epiderm and periderm is called the
skin of the plant.

29. • Epidemal hairs are extensions of
epidermal cells called trichomes.
• The epidermis in plant leaves and stems
also contain pores called stomata.
• Guard cells in the epidermis regulate
gaseous exchange between the plant and
the environment by controlling the size of
the stomata openings.

30. Functions of Epidermis: The epidermis
serves several functions:
• it protects stem against water loss,
• regulate gas exchange,
• secretes metabolic compounds,

31. Epidermis

32. 2-Ground Tissue: (arise from ground meristem
i.e primary meristem)
• The ground tissue of plants includes all
tissues that are neither dermal nor
vascular.
• This tissue is mainly composed of
parenchyma cells and also contains
collenchyma and sclerenchyma cells.

33. Functions:
• Ground tissue generates and
stores plant nutrients.
• Give support to stem.

34. • Ground Tissues consists of two main portions.
• (a) Cortex: while the layer of tissue between
the vascular tissue and the epidermis is known
as the cortex.
• (b) Pith: The ground tissue towards the interior
of the vascular tissue in a stem or root is
known as pith,

35. (a) Cortex: Tissue of unspecialized cells lying
between the epidermis (surface cells) and the
vascular, or conducting, tissues of stems and
roots.
Cortical cells may contain stored carbohydrates
or other substances such as resins, latex,
essential oils, and tannins.

36. • Cortex consists of
• 1- Hypodermis: hypodermis (exodermis) The
outermost layer of cells in the plant cortex,
lying immediately below the epidermis.
• Function: These cells are sometimes modified
to give additional structural support or to store
food materials or water.

37. • 2- Endodermis: The endodermis is the central,
innermost layer of cortex in land plants.
• It is a cylinder of compact living cells, the
radial walls of which are impregnated with
hydrophobic substances (Casparian strip) to
restrict apoplastic flow of water to the inside.

38. (b) Pith: The soft, spongy tissue in the center of
the stems of most flowering plants,composed of
parenchyma cells.
• In plants with woody stems, the pith dries out
and often disintegrates as the plant grows
older, leaving the stem hollow.
Functions: Store and transport nutrients
throughout the plant.

39. 3-Vascular Tissue:
• Vascular tissue is composed of xylem
and phloem. These tube-like
structures transport water and
nutrients throughout the plant.
• Vascular Tissue System

40. • Xylem : consists of two types of cells
known as tracheids and vessel elements.
Tracheids and vessel elements form tube-
shaped structures that provide pathways
for water and minerals to travel from the
roots to the leaves. While tracheids are
found in all vascular plants, vessels are
found only in angiosperms.

41. • Phloem: is composed mostly of cells
called sieve-tube cells and
companion cells. These cells assist in
the transport of sugar and nutrients
produced during photosynthesis from
the leaves to other parts of the plant.

42. Pericycle: The pericycle is a cylinder
of parenchyma or sclerenchyma cells
that lies just inside the endodermis and
is the outer most part of the stele of
plants.
• The stele is composed of mainly
three tissues which are the pericycle,
the xylem, and the phloem.

43. Functions of Pericycle:
• The sclerenchymatous pericycle
provides mechanical strength to
the young stem.
• The parenchymatous pericycle
stores food.

44. Differences between Monocot and dicot stem
No. Basic Terms Monocot Stem Dicot Stem
1 Epidermal
Hair
Present Absent or present.
2 Trichomes Lack trichomes Contain trichomes
3 Vascular
Bundles
Arrangement
Scattered within
the stem.
Arranged in a ring
shape.
Differences between Monocot and dicot stem

45. Differences between Monocot and dicot stem
N
o.
Basic Terms Monocot Stem Dicot Stem
4 Number of
Vascular Bundles
Numerous
vascular bundles
4-8 vascular bundles
5 Size of Vascular
Bundles
Inner vascular
bundles are larger
than outer
vascular bundles.
Vascular bundles
have equal size
6 Xylem Elements Have circular
shape
Have polygonal shape
Differences between Monocot and dicot stem

46. Differences between Monocot and dicot stem
No. Basic Terms Monocot Stem Dicot Stem
7 Pith Absent Present
8 Pericycle Absent Present
9 Differentiation
of Ground
Tissue
Not
differentiate
d.
Differentiated
into steler and
extra-steler
tissue.
Differences between Monocot and dicot stem

47. Differences between Monocot and dicot stem
N
o.
Basic Terms Monocot Stem Dicot Stem
1
0
Hypodermis Sclerenchymato
us
Chlorenchymatous
11 Silica
deposition in
the Epidermis
Do not undergo
silica deposition
Undergo silica
deposition
1
2
Strength of
Stem
Hollow at the
center
Solid stem
Differences between Monocot and dicot stem

49. ROOT
• Root, in botany, that part of a vascular plant
normally underground.
• Its primary functions are
• Anchorage of the plant,
• Absorption of water and dissolved minerals
• Conduction of these to the stem, and storage of
reserve foods.

50. • Difference from Stem: The root
differs from the stem mainly by
lacking leaf scars and buds, having a
root cap, and having branches that
originate from internal tissue rather
than from buds.

51. Structure of Root: The primary tissues
of the root are, from outermost to
innermost,
• 1- Epidermal Tissue
• 2- Ground Tissue
• 3- Vascular cylinder

52. 1- Epidermal Tissue: The epidermis is
composed of thin-walled cells and is
usually only one cell layer thick. It is
also called epiblema in root.

53. Functions: The absorption of water and
dissolved minerals occurs through the
epidermis, a process greatly enhanced
in most land plants by the presence of
root hairs.
Root hairs are slender, tubular
extensions of the epidermal cell wall.

54. 2- Ground Tissue :Inside the root, the
ground tissue forms two regions:
• Cortex: The cortex is between the
epidermis and the vascular tissue
• Pith : Pith lies between the vascular
tissue and the center of the root.

55. • Compared to stems, roots have lots of
cortex and little pith.
• Functions: Both regions include cells
that store photosynthetic products.

56. 3- Vascular Tissue: The vascular tissue
in the root is arranged in the inner
portion of the root, which is called the
stele.

57. • The outermost cell layer of the root’s
vascular tissue is the pericycle, an
area that can give rise to lateral roots.
In dicot roots, the xylem and phloem
of the stele are arranged alternately in
an X shape, whereas in monocot
roots, the vascular tissue is arranged
in a ring around the pith.

58. ROOTS
• Root Hair
• Epiblema
• Cortex
• Endodermis
• Phloem
• Pith
• Xylem

59. Differences between Monocot and Dicot Root
No. Basic Term Dicot Root Monocot Root
1 Epidermal
Covering
Covered by
exodermis
Covered by cortex
cambium
2 Cortex Wide and
consists of
parenchyma cells
only.
Narrow with
parenchyma and
sclerenchyma cells.
3 Endoder
mis
Less thick with
prominent
Casparian strips.
Thicker with less
prominent
Casparian strips.

60. No. Basic Term Dicot Root Monocot Root
4 Vascular
Bundles
Range from
two to six.
Numerous in
number.
5 Xylem
Shape
Polygonal Oval
6 Pith Less developed
or reduced.
More developed
and prominent.

61. No. Basic Term Dicot Root Monocot Root
7 Secondary
Growth
Present due to
cambium
Absent due to lack of
cambium
8 Silica
Disposition
on
Epidermis
Absent Present
9 Hypodermi
s
Collenchyma tissues Sclerenchyma tissues
10 Examples Beans, pea, and
peanuts, etc. have
dicot roots.
Banana, maize, and
palm, etc. are examples
of monocot roots.