Transcript Compound leaves

MORPHOLOGY OF VEGETATIVE
ORGANS
Assistant professor Ludmila
Anatolyevna Liubakouskaya
Botany and Ecology Chair
Introduction to pharmaceutical botany
• Pharmaceutical botany is the discipline forming
theoretical knowledge of flora and practical skills of
plants analysis necessary in future work of the
specialist pharmacist.
• Botany as a science, studies an external and internal
structure of plants, characteristics of processes of vital
activities, classification, interrelation with
environmental conditions, distribution, significance in
nature and human life.
• Complex studies of plants caused need to separate
from botany fundamental disciplines important for
pharmacy
Meaning of Botany for Pharmacy:
• Anatomy of plants – basis of microscopical analysis of
medicinal plant raw material.
• Morphology – basis of macroscopical analisys of medicinal
plant raw material.
• Physiology of plants is necessary for studying the metabolism
and the accumulation of biologically active substances.
• Systematic of plants is necessary for identification plants in
nature.
• Botanical Geographic – is basis of rational storing medicinal
herbs.
• Ecology of plants – on introduction plants into the culture.
Basic plant parts
Vegetative organs
• Vegetative organs of plants
are the organs performing
main functions of nutrition
and metabolism with the
environment.
• Vegetative organs include:
- the leafy-stem spears
providing photosynthesis;
- roots providing water supply
and mineral nutrition.
Structure of the root
• The main root and side
roots are distinguished
in a root. The primary
root is formed in a
germ, it is focused
down and becomes the
main root in
gymnospermous and
floral plants.
• Side roots are formed
on the main root.
Root system
• Types of Roots (based on
position and origin)Primary or
seed root - the first root to grow
from the radicle of embryo; tip of
main root axis.
• Secondary - any root sprouting
from the pericycle within the
primary root; lateral roots.
• Adventitious - Arising from organ
other than root, such as the
lower portion of the stem; usually
lateral.
The types of root systems
• tap-root systemconsists of one large,
thick root that anchors
the plant
• fibrous root system in
which dozens of
smaller, tendril like
roots form a system to
anchor the plant into
the ground.
The types of root systems
• Tap root system —
It is the root system that develops
from the radicle and continues as
the primary root (tap root) which
gives off lateral roots.
• Fibrous root system —
In this root system, the primary
root is short lived. A cluster of
slender, fiber-like roots arises
from the base of the radicle and
plumule which constitute the
fibrous root system.
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Fibrous root system is the main root
system of monocots, e.g. maize,
grasses, wheat.
Modifications of roots
Macroscopic diagnostic features:
• Roots (Radices), rhizomes (Rhizomata), tubers
(Tubera), bulbs (Bulbi), corms(Bulbotubera) are dried
out or fresh underground organs of perennial plants,
which are clean from the soil and free from traces of
stems and leaves.
• Size and form
• The features of surface and fissure(fracture)
• The color of surface on a fresh fissure(fracture)
• Smell and taste
А shoot - stem of a plant with leaves
A stalk, an axis of higher plants, making a spear together with
the leaves, serves for transport of water and organic
substances between roots and leaves
The main function of the stalk is transport of mineral substances
dissolved in water from the root to leaves, buds, flowers (the
ascending flow) and organic substances – photosynthesis products to
the root (the descending flow).
Besides the main function, the spear also performs other functions:
a) Supporting function – it provides a plant position in the
environment;
b) Assimilating function – young spears participate in photosynthesis;
c) Accumulating function– in a stalk nutrients are accumulated in
reserve.
Structure of the stalk
The parts of a plant. Note stem,
leaf, and petiole.
Structure of the stalk
• parts of a stalk from which side
organs branch (branches, leaves
and etc.) are called nodes, the
parts between the nodes are
called internodes.
• Stalks have metameric structure
• Growth of a stalk in length is
carried out owing to:
• - activity of the top meristem of
the spear, (cone of increase.)
• - intercalary (inserted) (for
example, in cereals).
The location of a stem in a space:
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1 — upright,
2 — clinging,
3 — twisting,
4 — climbing with
suckers,
• 5 — creeping,
• 6 — trailing
The type of ramification:
• 1-2 — tip branching, forked
increase(equal- and anisoforked);
3-5 — lateral branching,
monopodial increase with
alternative (3), opposite (4) and
whorled (5) location of lateral
axes; 6-8 — lateral branching,
monochasial (6), dichasial or
falseforked(7), pleiochasial(8)
increase; 9 — tillering;10 —
columnar stem
The form of cross-section:
• 1 - cylindrical;
• 2 - elliptical;
• 3 – rounded
tetrahedral;
• 4 – concave tetrahedral;
5 - trihedral;
• 6 - polyhedral;
• 7 - articulate;
• 8 - grooved
Types of modified stems
Types of modified stems
Macroscopic diagnostic features of stems:
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-The location of a stem in a space
-The type of ramification
-The phyllotaxy
-The form of cross-section
-Sizes (length and diameter at a base)
-The features of surface, pubescence.
Leaves (function, structure)
Different types of leaves
The dicotyledonous leaf
• A typical leaf of a
dicotyledonous plant
consists of two main
parts :
• the blade
• the petiole
• The blade includes an
apex, a margin, a vein
and a base.
Structure of a leaf
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Simple leaves have a single blade.
tip - the terminal point of the leaf.
blade - the flattened, green,
expanded portion of a leaf.
margin - edge of a leaf.
midrib - the most prominent central
vein in a leaf.
lateral veins - secondary veins in a
leaf.
petiole - the leaf stalk (connects
blade to stem).
stipules - leaf-like appendages (at the
base of the petiole of some leaves).
They may protect the young leaf and
may be modified
into spines or tendrils.
Types of leaves on an attachment to a stalk
Leaflet Arrangement on Petiole
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Simple – Leaf blade is one continuous unit
(cherry, maple, and elm)
Compound – Several leaflets arise from
the same petiole
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Pinnately compound – Leaflets arranged
on both sides of a common rachis (leaf
stalk), like a feather (mountain ash)
Palmately compound – Leaflets radiate
from one central point (Ohio buckeye and
horse chestnut)
Double pinnately compound – Double set
of compound leaflets
Forms of a blade
• The form of a blade is
determined by
proportion of the length
to the width in the
widest part of the
blade.
• For example: lanceolate,
ovate, peltate, linear,
reniform, orbiculate
cordate, hastate, spatulate
Leaf Shapes
Leaf shapes
Leaf Arrangement on Stems
• Alternate – Arranged in
staggered fashion along
stem (willow)
• Opposite – Pair of leaves
arranged across from each
other on stem (maple)
• Whorled – Arranged in a
ring (catalpa)
• Rosette – Spiral cluster of
leaves arranged at the base
(or crown) (dandelion)
Leaf margins
Margin Types
Margin of the leaf (Leaf edges)
• Leaf edges vary
markedly, depending on
the shape and depth of
their indentations
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crenate
Leaf edge with rounded teeth.
lobate
Leaf edge indented with deep notches.
entire
Leaf edge with no indentations.
ciliate
Leaf edge surrounded by short thin hairs called cilia.
doubly dentate
Leaf edged with teeth of different sizes, the main tooth
often having smaller teeth.
dentate
Leaf edged with pointy teeth of similar size.
Margin Types
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crenate
Leaf edge with rounded teeth.
lobate
Leaf edge indented with deep notches.
entire
Leaf edge with no indentations.
ciliate
Leaf edge surrounded by short thin
hairs called cilia.
doubly dentate
Leaf edged with teeth of different sizes,
the main tooth often having smaller
teeth.
dentate
Leaf edged with pointy teeth of similar
size.
Shape of Leaf Apex and Base
Leaf Tip Shapes.
Leaf Base Shapes.
Leaf venation (arrangement of veins)
• pinnate venation - feather-like,
net venation with lateral veins
extending from a central midrib.
• palmate venation - finger-like,
net venation with several major
veins diverging from the union of
the petiole and the leaf blade.
• parallel venation - principal veins
parallel to the axis of the leaf.
• Dichotomous venation –
Somewhat parallel vein sections,
forming a 'Y', found in Ginkgo
trees.
Simple and compound leaf
• In simple leaves, the leaf
surface is not divided into
leaflets. It has only one blade
or lamina. The leaves of
papaya, mango and money
plant are simple leaves.
• In compound leaves, the leaf
lamina is divided and is not a
unit. A leaf with more than
one blade is known as a
compound leaf. The blades of
a compound leaf are called
leaflets. Rose, neem and
walnut have compound leaves.
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Compound leaves
• Compound leaves have a blade
divided into individual leaflets.
• leaflet - secondary leaf of a
compound leaf.
• rachis - an extension of the
petiole bearing leaflets.
• petiolule - the leaflet stalk.
• petiole - the leaf stalk
• lateral veins - secondary veins in
a leaf.
• stipules - leaf-like appendages (at
the base of petiole of some
leaves).
Compound leaves
• Leaves are the major site for
photosynthesis in most
plants. The flat leaf blade is
specialized for catching
sunlight.
• Leaf characteristics vary
greatly from plant to plant
and are useful in
classification and
identification.
• Leaves are
either Simple or Compound
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Type compound leaves
• Leaves with blades
divided into several
distinct sections, called
folioles, the
arrangement of which
determines the leaf
type.
Difference between simple leaves and compound
leaves, simple and compound leaf forms
Simple leaf
Compound leaf
1. Consists of a single lamina.
2. The bud is usually present at
the leaf axil.
3. Stipules may be present at
the base.
Examples: mango, peepal, guava
Consists of several leaflets.
The bud is not present at the
axils of the leaflets.
Stipules are not present at the
base of the leaflets.
Examples: neem, rose,
tamarind
Conclusion
Examples of plants
Modification of leaves
• Thank you for attention!
• One moment please!
• For practical class you must have an album,
coloured pencils, a pen, lead pencil, a rubber,
an exersise – book.
• Guidelines in botany will be presented on the
information stend of the botany chair on the
third floor.