1. Study of Flowering Plants
SEMI-TECHNICAL DESCRIPTION OF A TYPICAL FLOWERING PLANT
Study and describe three locally available common flowering plants from each of the following families (Solanaceae, Fabaceae and Liliaceae) including dissection and display of floral whorls and anther and ovary to show
number of chambers. Types of root (Tap and Adventitious); Stem (Herbaceous/woody); Leaf (arrangement
shape, venation, simple and compound).
 The description has to be brief, in a simple and scientific language and presented in a proper sequence.
 The plant is described beginning with its habit, vegetative characters—roots, stem and leaves and
then floral characters inflorescence and flower parts.
 After describing various parts of plant, a floral diagram and a floral formula are presented. The floral
formula is represented by some symbols.
 In the floral formula, Br stands for bracteate, K stands for calyx, C for corolla, P for perianth, A for
androecium and G for Gynoecium, G for superior ovary and G for inferior ovary,
for male,
for
female,
for bisexual plants, + for actinomorphic and % for zygomorphic nature of flower.
 Fusion is indicated by enclosing the figure within bracket and adhesion by a line drawn above the
symbols of the floral parts.
STRUCTURE OF FLORAL DIAGRAM
 A floral diagram provides information about the number of parts of a
flower, their arrangement and the relation they have with one another.
(See Fig.)
 The position of the mother axis with respect to the flower is represented
by a dot on the top of the floral diagram.
 Calyx, corolla, androecium and gynoecium are drawn in successive whorls,
calyx being the outermost and the gynoecium being in the centre.
ROOT SYSTEM
Fig. Floral diagram
The roots of a plant constitute the root system. There are two types of root system, viz. tap root system
and fibrous root system.
(a) Tap Root System: In this root system, a single primary root comes out from
the base of the stem. The primary root develops from the radicle. Following are
the salient features of tap root system:
• The primary root develops from the radicle.
• The primary root bears branches and sub-branches which are called
secondary roots, tertiary roots and so on.
• The tertiary roots and further branches give out finer roots; called rootlets.
• Tap root system is one of the diagnostic features of dicotyledonous plants.
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P R A C T I C A L S K I L L S I N BIOLOGY- XI
Tap Root System
13
(b) Fibrous Root System: In this root system, hundreds of roots emerge from
the base of the stem. When the fibrous roots emerge from other plant parts,
they are called adventitious roots. Following are the salient features of fibrous
root system.
• Fibrous roots do not develop from radicle.
• When the primary root stops growing and does not become the main root
of a plant; it is replaced by fibrous roots.
• A fibrous root does not have branches.
• Fibrous roots are much slender than tap root.
• The fibrous root system is one of the diagnostic features of monocotyledonos
plants.
PARTS OF A LEAF
Fibrous Root System
Apex
Lamina
A typical leaf shows following structures:
Margin
(a) Leaf Base: It is the basal part of leaf. The leaf is
attached to the node of a stem or branch by leaf base.
Midrib
In many plants; the leaf base may not be
distinguishable from the petiole. But in some plants;
Vein
the leaf base is swollen and forms a cushion-like
Petiole
structure called pulvinus, e.g., legumes. In majority
of the monocots, the leaf base of sessile leaves clasps.
Auxilliary Bud
They form a sheath-like structure around the stem.
Stipules
Such type of leaf base is called sheathing leaf base.
Leaf Base
In some dicots, the leaf base bears a pair of small
scale-like lateral outgrowths, called stipules.
(b) Petiole: The stalk of the leaf is called petiole. It is usually of cylindrical shape. It is a stout structure
and it raises the lamina above the stem so that the lamina is properly exposed to the sunlight. If
petiole is absent then the leaf is called sessile.
(c) Lamina: This is the flat portion of a leaf and is the most conspicuous part of a leaf. The lamina is
the site of photosynthesis and of exchange of gases. Large number of veins and veinlets are present
on the lamina.
Shape of Lamina: Following are the various shapes or outlines of lamina—
1. Acicular: Lamina is needle-shaped, long, narrow and cylindrical, e.g., pinus.
2. Cylindrical: Leaves are cylindrical but thick. The lamina may be pointed at interior end, e.g., onion.
3. Linear: Lamina is long, narrow and flat, like a ribbon. Margins are more or less parallel, e.g., grasses.
4. Lanceolate: Lamina is tapering towards base and apex; the tapering is more gradual towards the
apex. e.g., eucalyptus, oleander.
5. Oblanceolate: This is same as lanceolate but the tapering is more gradual towards the base.
6. Oval or Elliptical: Lamina appears like lanceolate but is broader and shorter, e.g., carissa, guava, jamun.
7. Ovate: Lamina is rounded at base and tapering towards apex, e.g., ocimum, shoe flower, banyan.
8. Obovate: Lamina is rounded at apex and tapering towards base, e.g., euphorbia, acyranthes, jackfruit.
9. Subulate: Lamina is awl-shaped, long, narrower and tapering towards apex, e.g., isoetes.
10. Oblong: Lamina is almost rectangular in shape, e.g., banana.
11. Rhomboid or Rhombate: Lamina appears like a rhombus, e.g., Solanum nigram.
12. Cordate: Lamina is heart-shaped and base is notched, e.g., betel.
13. Obcordate: Lamina is heart-shaped and apex is notched, e.g., oxalis.
14. Orbicular or Rotund: Lamina is almost round in shape, e.g., Garden nasturtium.
15. Reniform: Lamina is kidney-shaped, e.g., Malva parviflora.
16. Lunate: Lamina looks like a half-moon and usually has two pointed basal lobes, e.g., Passiflora lunata.
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17. Spatulate: Lamina appears like a spatula, is rounded at apex and narrow towards base, e.g.,
calendula.
18. Cuneate: Lamina is wedge-shaped e.g., pistia.
19. Deltoid: Lamina is triangular in shape, e.g., Populus deltoides.
20. Hastate: Lamina is arrow-shaped and has two basal lobes which point outwards, e.g., Convolvulus
arrensis.
21. Sagittate: Lamina is arrow-shaped but lobes are pointed downwards, e.g., sagittaria.
22. Lyrate: Lamina is pinnatifid with apical lobes large and pointed, while lateral lobes become gradually
smaller towards the base, e.g., radish, mustard.
23. Runcinate: Same as lyrate but large and pointed lobes are at apex, while smaller lobes are pointed
towards the base, e.g., Launaea.
24. Oblique: The two halves of the lamina are unequal, e.g., dalbergia, neem.
25. Falcate: Lamina is flat, narrow and sickle-shaped e.g., eucalyptus, acacia.
Acicular
Obovate
Cylindrical
Linear
Subulate
Oblong
Orbicular or Rotund
Reniform
Lunate
Hastate
Sagittate
Lyrate
Lanceolate
Rhomboid or Rhombate
Oval or Elliptical
Cordate
Ovate
Obcordate
Spatulate
Cuneate
Deltoid
Runcinate
Oblique
Falcate
VENATION
The arrangement of veins in the lamina is called venation. There are two main types of venation,
viz. reticulate and parallel.
1. Reticulate Venation: In this type of venation, the main vein arises from the tip of the petiole.
The lateral branches of the main vein traverse the entire lamina. The branches further branch
out in veinlets and form a reticulate pattern all over the lamina. On the basis of number of main
veins, the reticulate venation can be of two types:
(a) Unicostate Reticulate Venation: There is a single main vein in this type. This is also called
the pinnate reticulate venation, e.g., peepal, mango, etc.
(b) Multicostate Reticulate Venation: In this type, there are more than one main vein. This is
also called palmate reticulate venation. This can be further divided into two types:
(i) Multicostate Reticulate Convergent Venation: In this type, main veins converge
towards the apex of the lamina, e.g., beri, tejpat.
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(ii) Multicostate Reticulate Divergent Venation: In this type, the main veins diverge towards
the apex of the lamina, e.g., arind, papaya, lufta, etc.
Unicostate
(Peepal)
Multicostate Convergent
(Zizyphus)
Multicostate Divergent
(Castor)
2. Parallel Venation: In this type, the veins which arise from the midrib don’t branch further and
run parallel to each other towards apex. Parallel venation is one of the diagnostic features of moncot
plants. Based on the number of main veins; the parallel venation can be divided into two types.
(a) Unicostate Parallel Venation: In this type, there is a single main vein. This is also called
pinnate parallel venation, e.g., canna, Musa pardisiaca.
(b) Multicostate Parallel Venation: In this type, there are many midribs arising from the tip of the
petiole. This is also called palmately parallel venation. This type can be further divided into two types:
(i) Multicostate Parallel Convergent Venation: In this type, the prominent veins converge
towards the apex, e.g., bamboo.
(ii) Multicostate Parallel Divergent Venation: In this type, the prominent veins diverge
towards the apex, e.g., palm.
Unicostate Parallel
(Banana)
Multicostate Convergent
(Bamboo)
Multicostate Divergent
(Palm)
TYPES OF LEAVES
Simple Leaf: A leaf is said to be simple, when its lamina is entire or when incised, the incisions do
not touch the midrib.
Compound Leaf: When the incisions of the lamina reach up to the midrib breaking it into a number of leaflets, the leaf is called compound.
A bud is present in the axil of petiole in both simple and compound leaves, but not in the axil of
leaflets of the compound leaf.
The compound leaves may be of two types:
Pinnately Compound Leaf: In a pinnately compound leaf, a number of leaflets are present on a common axis, the rachis, which represents the midrib of the leaf, as in neem.
Palmately Compound Leaf: In palmately compound leaves, the leaflets are attached at a common
point, i.e., at the tip of petiole, as in silk cotton.
Phyllotaxy
Phyllotaxy is the pattern of arrangement of leaves on the stem or branch. This is usually of three
types—alternate, opposite and whorled.
Alternate Arrangement of Leaves: In alternate type of phyllotaxy, a single leaf arises at each node
in alternate manner, as in China rose, mustard and sunflower plants.
Opposite Arrangement of Leaves: In opposite type, a pair of leaves arise at each node and lie opposite
to each other, as in Calotropis and guava plants.
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Whorled Arrangement of Leaves: If more than two leaves arise at a node and form a whorl, it is
called whorled, as in Alstonia.
Pinnate Compound
Leaves
Paripinnate
(Cassia)
Bifoliate
(Balances)
Imparipinnate
(Rose)
Trifoliate
(Oxalis)
Bipinnate
(Acacia)
Trifoliate
(Bel)
Tripinnate
(Moringa)
Quadrifoliate
(Paris quadrifolia)
Compound leaf of
Daucus
Quadrifoliate
(Marsilea)
Multifoliate
(Bombax)
THE INFLORESCENCE
The arrangement of flowers on the floral axis is termed as inflorescence.
Depending on whether the apex gets converted into a flower or continues to
grow, two major types of inflorescences are defined – racemose and cymose.
Racemose Inflorescence: In racemose type of inflorescences, the main
axis continues to grow, the flowers are borne laterally in an acropetal
succession. Acropetal succession means that older flowers are at the base
and younger flowers are near the apex.
Cymose Inflorescence: In cymose type of inflorescence, the main axis
terminates in a flower, hence is limited in growth. The flowers are borne in
a basipetal order. In basipetal succession older flowers are at the apex and
younger flowers are near the base.
THE FLOWER
Racemose
Cymose
Fig. Inflorescence
Four Whorls of Flower
Calyx: The calyx is the outermost whorl of the
flower and the members are called sepals. Generally,
sepals are green, leaf like and protect the flower in
Petal
Stigma
the bud stage. The calyx may be gamosepalous
(sepals united) or polysepalous (sepals free).
Style
Corolla: Corolla is composed of petals. Petals Antheridium
are usually brightly coloured to attract insects for
Ovule
pollination. Like calyx, corolla may be also free
(gamopetalous) or united (polypetalous). The shape and
Sepal
colour of corolla vary greatly in plants. Corolla may be
tubular, bell-shaped, funnel-shaped or wheel-shaped.
Receptacle
Androecium: Androecium is composed of
Fig.
Structure
of
flower
stamens. Each stamen which represents the male
reproductive organ consists of a stalk or a filament and an anther. Each anther is usually bilobed and
each lobe has two chambers, the pollen-sacs. The pollen grains are produced in pollen-sacs. A sterile stamen
is called staminode.
Gynoecium: Gynoecium is the female reproductive part of the flower and is made up of one or more
carpels. A carpel consists of three parts namely stigma, style and ovary. Ovary is the enlarged basal part,
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on which lies the elongated tube, the style. The style connects the ovary to the stigma. The stigma is
usually at the tip of the style and is the receptive surface for pollen grains. Each ovary bears one or more
ovules attached to a flattened, cushion-like placenta.
When a flower has both androecium and gynoecium, it is bisexual. A flower having either only stamens
or only carpels is unisexual.
Symmetry of Flowers:
• Actinomorphic (radial symmetry): When a flower can be divided into two equal radial halves in any
radial plane passing through the centre, it is said to be actinomorphic, e.g., mustard, datura, chilli.
• Zygomorphic (bilateral symmetry): When it can be divided into two similar halves only in one particular
vertical plane, it is zygomorphic, e.g., pea, gulmohur, bean, Cassia.
• Asymmetric (irregular) if it cannot be divided into two similar halves by any vertical plane passing
through the centre, as in canna.
A flower may be trimerous, tetramerous or pentamerous when the floral appendages are in multiple of
3, 4 or 5, respectively. Flowers with bracts, reduced leaf found at the base of the pedicel, are called bracteate and those without bracts, ebracteate.
Type of Flower Based on Position of Ovary
Hypogynous Flower: In the hypogynous flower the gynoecium occupies the highest position while
the other parts are situated below it. The ovary in such flowers is said to be superior, e.g., mustard, china
rose and brinjal.
Perigynous Flower: If gynoecium is situated in the centre and other parts of the flower are located
on the rim of the thalamus almost at the same level, it is called perigynous. The ovary here is said to be
half inferior, e.g., plum, rose, peach.
Hypogynous
Perigynous
Epigynous
Fig. Position of Ovary
Epigynous Flower: In epigynous flowers, the margin of thalamus grows upward enclosing the ovary
completely and getting fused with it, the other parts of flower arise above the ovary. Hence, the ovary is
said to be inferior as in flowers of guava and cucumber, and the ray florets of sunflower.
Aestivation
The mode of arrangement of sepals or petals in floral bud with respect to the other members of the
same whorl is known as aestivation. The main types of aestivation are valvate, twisted, imbricate and
vexillary. Following figure depicts all types of aestivation.
(a) Valvate: When sepals or petals in a whorl just touch one another at the margin, without overlapping,
as in Calotropis, it is said to be valvate.
(b) Twisted: If one margin of the appendage
overlaps that of the next one and so on
as in china rose, lady’s finger and
cotton, it is called twisted.
(c) Imbricate: If the margins of sepals or
petals overlap one another but not in
any particular direction as in Cassia
Valvate
Twisted
Vexillary
and gulmohur, the aestivation is called
imbricate.
Fig. Aestivation
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(d) Vexillary: In pea and bean flowers, there are five petals, the largest (standard) overlaps the two
lateral petals (wings) which in turn overlap the two smallest anterior petals (keel); this type of
aestivation is known as vexillary or papilionaceous.
Type of Attachment of Androecium
Stamens of flower may be united with other members such as petals or among themselves.
(a) Epipetalous: When stamens are attached to the petals, they are epipetalous as in brinjal.
(b) Epiphyllous: When attached to the perianth as in the flowers of lily.
Arrangement of Stamens
The stamens in a flower may either remain free (polyandrous) or may be united in varying degrees.
(a) Monoadelphous: The stamens may be united into one bunch or one bundle as in china rose.
(b) Diadelphous: Stamens are in two bundles as in pea.
(c) Polyadelphous: Stamens are in more than two bundles as in citrus.
There may be a variation in the length of filaments within a flower, as in Salvia and mustard.
Arrangement of Gynoecium
(a) Apocarpous: When more than one carpel is present, they may be free (as in lotus and rose) and
are called apocarpous.
(b) Syncarpous: They are termed syncarpous when carpels are fused, as in mustard and tomato. After
fertilisation, the ovules develop into seeds and the ovary matures into a fruit.
Placentation
The arrangement of ovules within the ovary is
known as placentation. The placentation are of different
types namely, marginal, axile, parietal, basal, central and
free central.
(a) Marginal: In marginal placentation the placenta
forms a ridge along the ventral suture of the ovary
Marginal
Axile
Parietal
and the ovules are borne on this ridge forming two
rows, as in pea.
(b) Axile: When the placenta is axial and the ovules
are attached to it in a multilocular ovary, the
placentaion is said to be axile, as in china rose,
tomato and lemon.
(c) Parietal: In parietal placentation, the ovules
develop on the inner wall of the ovary or on
Basal
Free Central
peripheral part. Ovary is one-chambered but it
Fig. Placentation
becomes two-chambered due to the formation of
the false septum, e.g., mustard and Argemone. When the ovules are borne on central axis and
septa are absent, as in Dianthus and Primrose the placentation is called free central.
(d) Basal: In basal placentation, the placenta develops at the base of ovary and a single ovule is
attached to it, as in sunflower, marigold.
EXPERIMENT 1(A)
Objective
To study a plant of family Solanaceae.
Materials Required
Plant of Petunia alba containing flowers, forceps, magnifying glass, scalpel, etc.
Theory
The first step in identifying the family of a given plant is by noting down all characteristics of the flower.
After that type of other plant organs are observed to identify some broad characteristics.
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Procedure
Take a flower of the given plant. Notice its symmetry. With the help of forceps separate all floral parts and spread
them on a white sheet. Note down number of sepals, petals, stamens, and gynoecium. Note down if various floral
parts are fused or segregated. Notice the position of ovary in relation to the thalamus of the flower and how many
locules are there in the ovary. Make a transverse section of ovary to count number of chambers.
Observations of Flower
Flower: bisexual, actinomorphic.
Calyx: sepals five, gamosepalous (united), persistent, valvate aestivation.
Corolla: petals five, gamopetalous (united), valvate aestivation.
Androecium: stamens five, epipetalous, polyandrous, inserted, basifixed.
Gynoecium: bicarpellary, syncarpous; ovary superior, bilocular, placenta swollen with many ovules.
Floral Formula
+
K5C(5)A5G(2)
Observation of Other Plant Parts
• Tap root system is present, which indicates that the plant belongs to dicotyledonae.
• Leaves are showing reticulate venation, which is another characteristic feature of dicots. Leaves
are simple and alternate.
• Flowers are pentamerous.
Based on above observation the given plant can be classified as follows:
Classification
Division
Class
Family
Genus
Species
:
:
:
:
:
Angiospermae
Dicotyledonae
Solanaceae
Petunia
alba
Twig of petunia
Floral parts
Anther
Petal
Stigma
Flower
bud
Stem
Flower
Stamen
Filament
Style
Sepals
Leaf
Ovary
Thalamus
STAMEN
Stigma
Style
Ovary
FLORAL DIAGRAM
PISTILL
Fig. Petunia alba
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EXPERIMENT 1(B)
Objective
To study a plant of family Fabaceae (Papilionaceae).
Materials Required
Plant of Pisum sativum containing flowers, forceps, magnifying glass, scalpel, etc.
Theory
The first step in identifying the family of a given plant is by noting down all characteristics of the flower.
After that type of other plant organs are observed to identify some broad characteristics.
Procedure
Take a flower of the given plant. Notice its symmetry. With the help of forceps separate all floral parts and
spread them on a white sheet. Note down number of sepals, petals, stamens, and gynoecium. Note down if
various floral parts are fused or segregated. Notice the position of ovary in relation to the thalamus of the
flower and how many locules are there in the ovary.
Observations of Flower
Flower: Bisexual, zygomorphic, pedicilate, hypogynous, pentamerous, complete, cleistogamous.
Calyx: 5 Sepals, gamosepalous, valvate.
Corolla: 5 Petals, polypetalous, vexillary.
Androecium: 9 + 1 stamens, diadelphous, basifixed.
Gynoecium: Monocarpellary, unilocular, superior ovary.
Floral Formula:
%+
K(5) C1+2+(2) A(9)+1 G1
Observation of Other Plant Parts
• Tap root system is present, which indicates that the plant belongs to dicotyledonae.
• Leaves are showing reticulate venation, which is another characteristic feature of dicots. Leaves
are simple and opposite. Flowers are pentamerous.
Based on above observation the given plant can be classified as follows:
Classification
21
Division
: Angiospermae
Class
: Dicotyledonae
Family
: Fabaceae
Genus
: Pisum
Species
: sativum
P R A C T I C A L S K I L L S I N BIOLOGY- XI
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Tendrils
Flower
Petal
Leaves
Androecium
Stamens
Sepal
Joined
stamens
Foliaceous
stipule
Gynoecium
ANDROECIUM
FLOWER
FLOWERING TWIG
Standard
Stigma
Ovary
Wing
Style
Keel
Keel
GYNOECIUM
FLORAL DIAGRAM
PETALS SEPARATED
Fig. Pisum sativum
EXPERIMENT 1(C)
Objective
To study a plant of family Liliaceae.
Materials Required
Plant of Alium cepa containing flowers, forceps, magnifying glass, scalpel, etc.
Theory
The first step in identifying the family of a given plant is by noting down all characteristics of the flower.
After that type of other plant organs are observed to identify some broad characteristics.
Procedure
Take a flower of the given plant. Notice its symmetry. With the help of forceps separate all floral parts and
spread them on a white sheet. Note down number of sepals, petals, stamens, and gynoecium. Note down if
various floral parts are fused or segregated. Notice the position of ovary in relation to the thalamus of the
flower and how many locules are there in the ovary.
Observations of Flower
Flower: Bisexual, Actinomorphic, Pedicilate, Hypogynous, Trimerous, Complete, Bracteate
Inflorescence: Raceme
Perianth: 6 tepals (3+3), Gamotepalous, Petaloid, Imbricate aestivation
Androecium: 3 + 3 stamens, Polyanous, Dorsifixed, Filaments of central whorl are shorter than those
of outer whorl
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Gynoecium: Tricarpellary, syncarpous, superior ovary, stigma trilobed
Floral Formula:
+
+
P(3+3) A(3+3) G3
Observation of Other Plant Parts
•
•
•
•
Fibrous root system is present, which indicates that the plant belongs to monocotyledonae.
Leaves are showing parallel venation, which is another characteristic feature of dicots.
Flowers are trimerous.
Based on above observation the given plant can be classified as follows:
Classification
Division
Class
Family
Genus
Species
:
:
:
:
:
Angiospermae
Monocotyledonae
Liliaceae
Alium
cepa
Inflorescence
Leaf
Stamen
Gynoecium
Bulb
Adventitious
roots
INFLORESCENCE
ONION PLANT
Ovule
Stamens
Ovary
Placenta
T.S. OVARY
FLORAL DIAGRAM
SINGLE FLOWER
Fig. Alium cepa
VIVA VOCE QUESTIONS
Q1. Name some common plants which belong to the Solanaceae family.
Ans. Potato, tomato, brinjal.
Q2. Name some plants which belong to the Fabaceae family.
Ans. Black gram, soyabean, kidney beans.
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Q3.
Ans.
Q4.
Ans.
Q5.
Ans.
Q6.
Ans.
Q7.
Ans.
Q8.
Ans.
Q9.
Ans.
Q10.
Ans.
Q11.
Ans.
Q12.
Ans.
Q13.
Ans.
Q14.
Ans.
Q15.
Ans.
Q16.
Ans.
Q17.
Ans.
Q18.
Ans.
Q19.
Ans.
24
Name some plants which belong to the Liliaceae family.
Onion, garlic, asparagus, tulip.
Which set of characters of Solanaceae give a clue that it belongs to dicotyledons?
Tap root system and reticulate venation in leaves.
Which set of characters of Liliaceae give a clue that it belongs to monocotyledons?
Adventitious root system and parallel venation in leaves.
What do you understand by actinomorphic flower?
A flower showing radial symmetry is an actinomorphic flower.
What do you understand by zygomorphic flower?
A flower showing bilateral symmetry is a zygomorphic flower.
What do you undertsand by gamopetalous or gamosepetalous flower?
When petals or sepals are united at their ends they are said to be gamopetalous or gamosepalous
respectively.
What do you understand by aestivation?
The arrangement of sepals or petal with respect to one another is called aestivation.
What do you understand by a pentamerous flower?
When floral structures are present in 5’s or multiples of 5 then flower is said to be pentamerous
flower.
Which part of an angiospermic plant is the most important for its taxonomic study?
Flower is the most important part of an angiospermic plant for its taxonomic study.
What is the type of aestivation for petals in Pisum sativum?
In the Pisum sativum petals are arranged in vexillary aestivation. There is one standard petal
which overlaps two petals on both sides, called wings. Wings overlap the fifth petal, called keel.
In the case of onion, term tepal has been used instead of petals. Why?
Tepals are elements of the perianth, or outer part of a flower, which include the petals or sepals.
The term tepal is more often applied specifically when all segments of the perianth are of similar
shape and color, or undifferentiated, which is called perigone. When different types of organs can
be distinguished, they are referred to as petals and sepals.
Which type of information can be revealed by floral diagram?
Floral diagram gives a clue about following:
• Symmetry of flower,
• Arrangement of different whorls of flower,
• Position of ovary with respect to thalamus.
Fibrous root system is characteristic of which group of angiosperms?
Monocot.
Tap root system is characteristic of which group of angiosperm?
Dicot.
What do you understand by simple leaf?
When lamina of leaf is entire, or in case of incisions in the lamina, the incisions do not touch the
midrib, leaf is a type of simple leaf.
What do you understand by compound leaf?
When incisions in lamina touch the midrib, the leaf is a compound leaf.
What do you understand by pinnately compound leaf?
In pinnately compound leaf many leaflets are present on a common axis.
P R A C T I C A L S K I L L S I N BIOLOGY- XI
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What do you understand by palmately compound leaf?
In palmately compound leaf leaflets are attached to a common point.
What is acropetal succession of flower?
When older flowers are at base and younger flowers at top of the main axis, the arrangement is
called acropetal succession. This is found in racemose inflorescence.
What is basipetal succession of flower?
When older flowers are at the top and younger flowers are at the bottom of the main axis, the
arrangement is called basipetal succession. This is found in cymose inflorescence.
What are the various types of arrangement of ovary on thalamus?
Arrangement of ovary are of following types:
Hypogynous, Perigynous and Epigynous
What are the various types of aestivation?
Types of aestivation:
Valvate, Twisted, Imbricate and Vexillary
What are the various types of attachment of androecium?
Types of attachment of androecium:
Epipetalous and Epiphyllous
What are the various types of arrangement of stamens?
Types of arrangement of stamens:
Monoadelphous, Diadelphous and Polyadelphous
What are the various types of placentation?
Types of placentation:
Marginal, Axile, Parietal and Basal
EXPERIMENT 2(A)
Preparation and Study of T.S. of Dicot and Monocot Root and Stem (Only Primary Structure)
Objective
To study the T.S. of dicot stem.
Materials Required
Blade, petri dish, dropper, microscope, brush, forceps, filter paper or blotting paper, saffranin, glycerine,
slides, coverslips, dicot stem, etc.
Procedure
With the help of blade cut as many thin slices of the stem as
possible. Drop them in a petri dish full of water. Pick 3 or 4
slices with brush and place them on a slide. Put a few drops of
saffranin. Then remove excess water and stain with the help
of blotting paper. Now put some drops of glycerine. Put a coverslip
on slide, taking care that no air bubbles remain under the cover
slip. Observe under a compound microscope.
Epidermis
Hypodermis
Cortex
Medullary Ray
Vascular Bundle
Pith
Observations
Fig. T.S. of dicot stem
Following structures are visible in the T.S. of dicot stem:
Epidermis: The outermost layer is called epidermis. Hair like structures are seen on cuticle.
Appearance of thin cell wall means that cuticle is composed of parnechyma.
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