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Chap 1
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/ 47
Plant Morphology-1
(Root, Stem and Leaf)
‘The flowering plants are the most dominant plants on the earth today. About 3 lac
species of this group exist. They exhibit great variations in their siz, form, structure, etc.
Lemna is.a very small aquatic plant. Sequoia and Eucalyptus are very tall plants. Some
fare herbs, some are shrubs. Some are trees and some,
are climbers. Some are annuals whereas some are
perennials old. In their lifestyles, they may be xerophytic,
hydrophytic, epiphytic or parasitic.
‘The plants can be studied through their external
as well as their internal characters.
A typical flowering plant possesses an unbranched
or branched axis. From this axis, lateral appendages are
produced. The main axis is generally divided into two
parts — an underground part root and an above ground part
shoot. They are also called a root system and a shoot,
system, The root system develops from the radicle and
the shoot system develops from the plumule, The shoot
system consists of stem, leaves, flowers, etc. The flowers,
produce fruits and seeds. Seeds produce new plants.
(D Root + Root is the underground part of the
‘silly bod
‘Terminal bud
‘of branch
Vepeuive
branch
‘Typical plant
plant axis. It develops from the radicle. It is positively geotropic and hydrotropic and
negatively phototropic. It lacks chlorophyll.
The primary structure developing from the radicle is called primary root, From its
secondary and tertiary branches arise. If the primary root develops longer and stronger
than its branches then it is called a tap root. The root system developing from a tap root is called tap root system. In dicotyledonous
plants tap root system occurs.
A root developing from a radicle is called a normal root. A root developing from any part
other than the radicle is called an adventitious root. Such roots may develop from hypocotyl,
stem or leaf parts. In monocot plants, the primary root is shortlived. Later on thin fibrous roots
develop from the hypocotyl and the basal region of stem. Such roots are called fibrous roots
and the root system formed by them is called fibrous root system.
Regions of the Root
Regions of root include the apical meristematic region surrounded by protective rootcap,
the elongation region and the maturation region.
+ Root cap It surrounds the meristematic region
of the root apex e.g : Pandanus. In aquatic plants
like Pistia, it occurs asa loose covering which is
called root pocket.
+ Meristematic region : The cells of this region
undergo constant cell divisions and add new cells.
These cells are small with thin walled and filled
with protoplasm.
+ Region of Elongation : The cells of this
region increase rapidly in size and length and induce
growth in length and width,
Region of Maturation : The cells ofthis region
differentiates and form tissue structure. From this region
then delicate fibrous root hairs are produced. This region is also known as root hair
region. The new branches are produced from the permanent region located after this
region.
‘Normal Functions of Root
(@) Fixation + To fix the plant properly in the soil and to develop a proper hole in soil. (2) Absorption : To absorb water and various minerals from soil and to conduct them
to the base of stem axis.
‘Special functions of Root :
‘Special adaptations are essential for performing special functions. Such adaptations cause
‘modification in the concemed organs.
Modifications of roots for special functions
(1) Storage of food : Sometimes, the extra food prepared by leaves is stored in roots.
‘Such roots are underground, fleshy and of various shapes. The stored food helps the plant in tiding
‘over the dormancy.
(A) Modifications of tap roots : In Carrot, Radish and Beet, tap root stores food and
becomes fleshy. In earrot, the food storing root becomes conical. It is called conical tap root.
In Radish, it becomes fusiform in shape and hence it is called fusiform tap root. In Beet, entire
food is stored in the basal part of the root. Hence the root suddenly tapers into a thin thread-
like structure. Such a root is called napiform tap root.
Beet
Root : Modifications of tap roots for storage of food
(B) Modifications of adventitious fibrous roots : When a fibrous root stores
food and becomes fleshy, it is called a tuberous root.
In Sweet Potato, a creeper plant, isolated adventitious fibrous roots, developing from
the stem, become tuberous in shape. These roots have irregular shapes and are called simple,
‘tuberous, roots.
In Asparagus and Dahlia, tuberous roots occur in a cluster, Such clusters are called
fasciculated tuberous roots.
‘Sweet Potato - Simple tuberous root Dahlia - fesciculated tuberous root
Root- Modification for storage of food (2) Mechanical Support :
(A) Stilt roots : Im Malze and
Pandanus edventitious roots arise from node.
of the stem nearer to the ground. These roots
grow obliquely downwards, enter the soiJ and
provide mechanical support. The aeed for
additional support arises because the underground
root systems are superficial. These roots are
called stilt roots.
(B) Prop Roots : The root system of Banyan
tree possesses « strong hold in the soil. Its serial
branches grow borizootally. Gradually they become
thick and beavy. They may snap under their own
weight. To prevent this. prop roots develop. Prop roots
are rope-like and develop in groups. They grow
downwards, enter the soi) and develop prop roots
Later, they become thick and pillar-like.
@) Climbing + Plants growing as twinners and climbers
possess weak stems. They possess modified structures for
climbing. In Pothor, long branched or unbranched, brown
adventitious roots develop from nodes and internodes of the
stem. They are called climbing or clinging roots. They secrete
‘8 sticky material which helps them to stick to the support, and
helps them in climbing.
(@ Photosynthesis : Tinospora is a twinner and grows
very rapidly. Tbe leaves on the stem are few and small. They Pathos Root-Moilification
cannot fulfill the food requirement of plant. Thin, amooth, green for climbing
and thread like adventitious roots develop suspended from the
sem. These roots are called assimilatory roots. They carry out photosynthesis. (S) Breathing : The specialized groups of plants which inhabit the saline, waterlogged
soil of crecks near coastal regions are called Mangroves. Rhizophora and Avicennia are such
plants. They produce negatively geotropic and positively phototropic aerial roots from their
‘underground roots. These roots are spongy, loog and possess a lange number of lenticels. They
may be branched or unbranched. Sufficient oxygen reaches the underground root system
‘through these lenticels and the exchange of gases becomes easy. These roots are called
‘pneumatophores.
(© Absorption of Moisture : Some Orchids live as epiphytes on the branches of trees
in forests. They obiain only a habitat from the host. They do not obtain water, salts or
prepared food from the host. They have no contact with soil. They produce some adventitious
roots which remain suspended in ait. These roots are spongy, thick, long and greenish. A.
specialized velamen tissue occurs on their outer surface. The cells of this tissue are polygonal,
thick walled and arranged in many layers and absorb moisture from atmosphere. They are called
epiphytic roots. Cuscuta is a nongreen, leafless plant, Its stem is yellow and twining. It is a total parasite.
It develops suckers or haustoria at places of close contact with the host plant. Through these
haustoria it establishes direct contact between its own conducting tissues and the conducting
tissues of the host. These haustoria suck water, minerals and prepared food from the host. Such
‘suckers’ act as parasitic roots, Cuscuta is a total parasite,
Loranthus lives on the branches of trees like mango. It absorbs only water and minerals
‘rom host through its haustoria. As it possesses green leaves, it prepares its food using them. Thus
Loranthus is a partial parasite.
® Symbiosis : The leguminous plants like Bean, Groundnut
‘and others possess small or large nodules on their root systems. These
‘ae called root nodules. Nitrogen-fixing Rhizobium bacteria live in
these root modules. These bacteria convert atmospheric nitrogen
into absorbable salts through nitrogen fixation. These salts are available
to the plants. In return, the bacteria obtain a habitat and nutrition.
‘Such a mutually beneficial relationship is called symbiosis and the
roots are called symbiotic roots.
(©) Vegetative Propagation : Adventitious buds occur on
tuberous roots of plants like sweet potato take part in reproduction.
‘Symblosis-Root nodules Gi) Stem : It is the acrial part of plant axis. It develops from
plumule. It is negatively geotropic and hydrotropic and positively
Phototropic. It is distinguished into nodes and internodes. Leaves arise from nodes. The region
between two successive nodes is called internode. An apical bud occurs at the tip of stem. It
causes growth in elongation of main axis. An axillary bud occurs in the axil of a leaf. An axil
is the angle formed by a leaf with the stem at the node. In the beginning, the stem is green.
Branching
ey The development and arangeneat of tues
‘on stem is called branching. Two main types of
Hidicoll Digan branching occur :
(@) Dichotomous branching : The apical bud
continuously divides into two branches, which also
=a continue to do the same, e. g : Hyphaene (palm)
(2) Lateral branching : The branches are
produced on lateral sides, There are two types of
lateral branching — Racemose and Cymose.
Th racensose type of branching, the anilry boda
| on the main axis produce new branches continuously
Ee an
in an acropetal fashion.
‘Cymose/Racemose branching, Hyphaene ‘Potyalthes Vitis
‘These branches develop and also do the same. As a result the plant develops a conical or
‘a pyramidal shape. e.g. Polyalthea; Casuarina, As all the branches arise from a single
main axis, such an axis is called monopodial axis. In cymose type of branching, the apical
‘bud of the main axis becomes inactive after sometime, A branch develops from the axillary
‘bud located in the axil of the leaf just under it. If a single branch develops in this way,
it is called uniparous cymose branching, If all such branches are formed only on one side,
either right or left, it is called helicoid, uniparous branching, e. g: Ashoka. If the branches are
formed altemately both sides, it is called scorpioid, uniparous branching. e.g : Vitis. If two
‘branches develop, the branching is called biparous, cymose branching. e.g : Mirabilis,
Carissa, If more than two branches develop in this way, the branching is called multiparous,
‘eymose branching, ¢.g. : Red oleander, Croton. If the axis of the stem is formed by union
of many lateral branches, it is called a sympodial axis. e.g. Vitis.
Stem may be aerial or underground. Aerial stem in most plants is erect, strong and
‘woody. In some cases, the stems are delicate, threadlike and weak. Such plants either live
Prostrate on ground or they live as climbers or twinners. They develop special structures
for climbing.
‘Underground stems occur inside the soil. They are devoid of chlorophyll, and generally
possess small scaly leaves. They sometimes store food. In favourable season, they produce
aerial leaves. They also carry out vegetative propagation, The food stored in them provides
nourishment during dormancy period,
Normal Functions of Stem
(1) To arrange the leaves in such a way that they obtain sufficient light.
@) To arrange reproductive organs like flowers, fruits and seeds in such a way
that pollination, fertilization and dispersal of seeds can be properly carried out.
(@) To conduct water and minerals, absorbed by the roots, towards leaves and to
transport food prepared by leaves to other organs of the plant.
Special Functions of stem
Under specific condition, the stem performs special functions. They are as follow.
(1) Storage of food : Underground stems are modified for storage of food. In
Ginger, the underground stem grows parallel to the ground surface. It becomes fleshy through storage of food. It possesses nodes, internodes, scaly leaves and adventitious roots,
Such a modified stem is called rhizome or rootsiock. Another example of this kind is Tommecic.
In the axils of the underground sonly Jeaves of Potato plant tranches develop. They stove
food in thoir apical regions which become round or oval. These are called tubers. Buds with
sealy leaves oceur in the pits on tubers. These are called ‘eyes’. with the help of eyes they
‘ean carry out vegetative propagation. In Amorphophallus, condensed form of shizome
occurs which is called com. It is a food-storing structure made up of only ene intemnods.
Amorphopbaline
“Food storage stent
<2) Vegetnttve Propagation : These modifications are of subaetial steous. A patt of the
stem in underground and a remaining part is above ground, Im Gruss, Oxalis und Hycrocoryl,
‘thin long branches develop. They possess intemodes and rin parallel to the ground. From the
noxies which come in contact with ground, new planta are produced Thia modification is called
runner, In aquatic pleats, Pistia snd Etchhornia, short, thick md horizontal branches develop.
Such branches are called offsets. In Nephredepis and Strawberry branches arising tom basal
regions grow obiiguely Tike arches, come in contact with ground and produce new plants, These
‘branches are called stolons, In Mint vegetative propogation takes place by suckers,
@) Protection ¢ In some plants, the apical or the axillary bud develops into a sharp
pointed structure. Iris called thorn, They we protective, In Carizra, the apical bud is wansformed
into a bifld, leaflets thorn, In Lawsonia and Paseagramate, an axillary bud is transformed into
thom. Sometimes leaves and flowers are borne ox thorns. The pointed, curved sharp stmcsures ‘produced on the surface of stem in rose plant are called prickles. They are not modifications
of stem. They are outgrowths from surface.
Carissa - Thorn Rose - Prickles
@ Climbing : In Passion flower, Cucurbita, Bittergourd, etc. the axillary buds modified
into thin, long, threadlike structures. These are called Stem tendrils. They twine around the
support and help the plant in climbing.
Passion flower-Modification for climbing
(© Photosynthesis : Plants like Muehlenbeckia and Opuntia live in dry habitats.
‘They shed their leaves to reduce transpiration. Their stems become green, possess
chloroplasts and are generally flat. Such stems which carry out photosynthesis are called
phylloclades. 10
© Storage of food and reproduction : In Dioscorea and Agave plants, axiliary buds
and floral buds respectively store food and become fleshy. Later on they separate from the
parental plant and produce new plants. Such a modified bud is called bulbil.
(DD Lest : A leaf is a flat, green and broad lateral appandage developing from the node
of a stem or its branch. It possesses an axillary bud in its axil, Tt has determinate growth,
‘There are three parts in a typical leaf — leaf base,
petiole and lamina. The leaf remains attached to the stem at
node through the leafbase. Sometimes a pur of lateral outgrowths
develops fram the leaf base. They are small and leaf-like.
These are called stipules. In plants like Maize, the leafbase
expands into a sheath which covers the nodal region. Itis called
sheathing leaf base. A stalk-like region connecting the leafbase
and the lamina is called petiole. Tt supports the lamina and
arranges it for securing proper light. If a petiole occurs, the
leaf is called petiolate. If the petiole is absent, the leaf is
called sessile. Generally the petiole is round and cylindrical.
Lamina is the main part of the leaf. It is broad, flat and
green, Veins are distributed in it, There is a great variation in
size, shape, margin incision, etc. of lamina. The arrangement
of veins and veinlets in lamina is called venation.
‘Reticulate venation
‘Two main types of venation occur - Reticulate venation and Parallel venation.
Reticulate venation is observed in dicotyledon leaves. Monocotyledon leaves possess parallel
‘venation, Conducting tissues occur in veins. Both these types of venation are further divided into ‘two types - unicostate and multicostate. Multicostate venation can be either converging or
diverging. The veins transport water, soluble minerals and prepared food. They also form a
skeletal network in the lamina,
Simple leaf and compound leaf
If a single lamina occurs in a leaf, it is called a simple leaf. It has an axillary bud in
its axil. Sometimes, the lamina appears dissected from the margin. Such incisions divide the
Jamina to a lesser or a greater degree. However, this incision is not complete. If this incision
reaches the midrib or the tip of the petiole, the lamina is divided into independent leaflets.
‘Such a leaf is called a compound leaf. The leaflets of a compound leaf do not possess axillary
buds.
‘A compound leaf may be pinnate or palmate. In a pinnate compound leaf, the leaflets
are arranged on both lateral sides of the main vein or midrib. In a palmate compound leaf, the
Jeaflets are arranged on the tip of the petiole. If a single leaflet is so arranged, the leaf is called
‘nifoliate palmate compound leaf (e.g : Lemon). If two leaflets occur, it i called bifoliate, palmate
compound leaf (eg : Balanites) and if many leaflets are thus arranged, it is called multifoliate
palmate compound leaf (e.g : Bombax, Aegle). In a pinnate compound leaf, if the leaflets are
arranged directly on the main midrib, tis called unipinnate compound leaf (e.g. Cassia). Ifthe
‘midrib branches and the leaflets are arranged on these secondary branches, the Ieaf is called
bipinnate compound leaf (e.g. : Caesalpinia, Acacia) and if the leaflets are arranged on tertiary
or higher order branches, the leaf is called multipinnate compound leaf
(e.g. Moringa).
‘There are some other types of leaves also. The leaf included within a seed is called
cotyledon or seedleaf; very small, reduced and papery leaf is called scaly leaf; the leaf from
the axil of which a flower develops is called bract. Stamen and carpel are called sporophylls
prey
Palmate compound leaf
Unipinnate compound leaf Bipinnate compound leaf
Ww |Bifoliate palmate compound Lent ‘Muttfoliate patmate compound leat
The arrangement of leaves on stam or on its branches is called phyliotaxy. If a single leaf
sminea from m node, the phyllotrry is called altemats eg., Mustard, Sunflower, Hibiscus. In
‘ame plants, two loaves scise opposite to each other from a node, This phyllotaxy is called
‘opposite. When ths pairs of leaves on successive nodes are arranged at right angle to each other,
the phyllouny is callod opporite deoumate, «1g. Calotropis. If tho peir of loaves om sucocative
odes ere arranged overlapping, one smother, the phyllotrry is called opposite superimposed,
Og Qulsqualts, Guava. If more than two lenves ace scmaged at each node, the phyllotaxy
is called whoried, eg. Red oleander, Alstonia. Normal Functions of Leaf
() To prepare food by carrying out photosynthesis
(2) To arrange gaseous exchange for respiration.
(B) The loss of water in the form of water vapour (transpiration) occurs through leaves
Special Functions of Leaf
In addition to their normal functions, leaves perform special functions in some plants.
They possess modified structures for these functions.
(@) Storage of food + In Onion, the stem is condensed,
underground and disc-like, Leaves are arranged concentrically.
‘The main part of leaf is aerial and green. It prepares food. The
{food is stored in the leaf base. The leaf bases of inner leaves
become fleshy. The peripheral leaf bases remain dry and
papery. Such a food storing structure is called a tnicated
bulb.
(2) Support and climbing : In some plants which
possess weak stems, the entire leaf or its part is utilised for
climbing.
13 In Gloriosa, the leaf apex becomes tendrillar. In Smilax, the stipules become tendrillar.
In Pea, the terminal leaflets of a compound leaf become tendrillar. In Bignonia, three terminal
leaflets become hook-like or clawed. Tendrils twine around a support and help the plant in
Leal-Modification for climbing
(@ Protection : In some plants leaf or some part of the leaf is transformed into a sharp
pointed structure which provides protection against grazing animals, In Acacia and Zizyphus.
the stipules become spiny. In Agave, the leaf apex becomes spiny. In Opuntia, the entire
leaf becomes a spine.
‘Agave
Leaf Modification for protection es |: le
(@) Photosynthesis : Photosynthesis is a normal function of leaf. However, it is
carried out mainly by the lamina, In Pea, stipules become leaflike and carry out photosynthesis.
‘They are called foliaceous stipules. In Australian acacia, the petiole becomes green and
flat and prepares food. It is called phyllode.
(5) Insectivory : In the
insectivorous plant, Nepenthes, the leaf is
modified into a pitcher. In Utricularia, the
leaf is modified into a bladder. These
structures are useful in capturing insects.
‘Nepenthes
Summary
‘The flowering plants are most dominant plants on the earth today. They exhibit great
variation in their external morphology. They have well developed shoot and root systems,
Root system is positively geotropic and hydrotropic and negatively phototropic. It develops
‘from the radical. Root systems may be either tap root or fibrous root. Generally dicot plants
have tap root system and monocot plants have fibrous root system. Root possesses root cap,
‘meristematics region, region of elongation and region of maturation. The main functions of the
root system are fixation of plant in the soil and absorption of water and mineral from the
soil.
Roots are modified for various functions like storage of food, mechanical support,
climbing, photosynthesis, respiration, absorption of moisture, parasitism and symbiosis and
reproduction.
‘The shoot system is developed from plumule. It is negatively geotropic, positively
phototropic and negatively hydrotropic. The shoot system is diffentiated into stem, leaves,
flowers and fruits. Stem possesses nodes, internodes, leaves, hairs and axillary and apical 16
Exercise
1, Put a dark colour in a given circle for correct answer :
wo
@
@
@
o
©
@
Root is...
(A) Positively phototropic Q(B). Positively geotropic
(© Negatively hydrotropic ©) (D)_ None of this
Root pocket is found in which of the following plants ?
(A) Pandanus OO. ®) Pistia
(©) Maize O ©) Radish
Example of fusiform tap root i
(A) Radish OO ® Beet
(©) Carrot OO ©) Sweet potato
Fasciculated tuberous root is found in......
(A) Dahlia OO ® Beet
(©) Sweet potato O © Maize
Funetion of prop root is...
(A) Reproduction OO ©®) Cimbing
(©) Support O ©) Food storage
Which of the following plants is an incomplete parasite ?
(A) Rhizophora OB) Tinospora
(C) Loranthus OO ©) Cascuta
In which type of branching, apical bud becomes inactive after sometimes
(A) Racemose OO ® Cymose
(©) Monopodial (D)Sympodial
Oo
Function of turmeric is ... .
(A) Protection © @®) Reproduction
(©) Food storage OO ®) Gimbing
00 00 00 00 00 OO
oO OO 6.
(©) Which of the following plants possesses Rhizobium bacteria ?
(A) Orchid OO ®) Bean fo)
(©) Tinospora OO ®) Cascuta fo)
(0) Which of the following plants possesses photosynthetic root ?
(A) Banyan © ®) Rhizophora O°
(©) Tinospora © ©) Pandanus Oo
‘Answer in short :
Q) Which parts produce root system and shoot system ?
(2) Mention the regions of root.
(3) What are Mangroves ? Give examples.
(4) Give the examples of insectivorous plants.
Define with suitable example :
Tuberous root, Adventitious root, Epiphytic root, Rhizome, Tuber, Runner, Offset, Stolon,
Stem tendril, Bulbil, Stipule.
Describe the special modifications of root, stem and leaf with examples for
G) Storage of food 2) Climbing
@)_Phowosynthesis
Explain the following terms :
Root pocket, Epiphyte, Symbiosis, Branching, Thom, Spine, Prickle, Stolon, Bulbil,
Phylloclade, Stipules, Compound leaf, Phyllotaxy, Phyllode.
Write short notes on :
Normal functions of Root, Symbiotic Root, Stilt roots, Normal functions of Stem, Clinging
roots, Venation, Photosynthetic roots, Phyllotaxy, Pneumatophores, Normal functions of
leaf, Parasitic root, Insectivory, Typical leaf
Draw labelled diagrams of =
(1) _ Various regions of root. @) Typical Leaf
) Typical angiosperm plant
Distinguish between :
(1) Tap root system - Fibrous root system
@) Roots of Cuscuta and Orchid OR Parasitic root and Hygroscopic root,
@) Simple leaf and Compound lear
(4) Pinnate compound Jeaf and Palmate compound leaf
7 18
Plant Morphology-2
(Flower, Fruit, Seed and Family)
‘We have so far discussed the vegetative orguny of the plant in Chapter 1; now we
omdy the reproductive parts of lowers in this chapter
‘As the young plants grow and the vegetative parts mature, flowers make their appear-
vmncca in order to produce sccds end thus, pave way for the next generation. The vegctntive
growth leads to the development of tranches snd foliages. Some of these muture shoots
start bearing flowers and are known as reproductive shoots,
Inflorescence
‘The axis af a plant which bears Flowart is called peduncle or rachis. The arrangement
of flowers on the rachis is called inflorescence, It is also termed aa Anthotaxy. An inflo-
rescence may be apical or axillary. There are two main types of inflosescence
(A) Recemose and (B) Cymors,
(A) Rncomoss Inflorescence : Tn this type of inflorescence the apical bud is not
‘transformed into a flower, I goea on producing new flowers in an acropetal succession on
‘tho rachis, The lowers towards the bese develop ewlior end are Jerger. Then the process
gradually progresscs towards the apex.
Recomoee Inflorescence ix of different
types. Some common types are as
follow:
(@) Receme : When pedkmele or
machin is nomally elongated and flowers
0 stalked, ths inflorescence in called a
ruceme, 6g, Mustard, Caesalpinia @ Splke : When peduncle or
‘chia in nomully elongated but flowers
ae seusile, the inflomecence is called
a spile c.g. Achyronthus.
sbove the fomale flowers. Sometimes stailo flowers sco present between
male md femule flowers. The peduncle is protected by a large foliage
tract known as spate ©.z, Colocasia, Musa,
@ Catlin ¢ IF the axis of # spike is weak and doos not stand erect
‘but is pendilous ‘Spadix~ Colocasia
and all the flower in an
inflorescence aro unisexual, the
infloreaconce in called Catkin
‘Mulberry, Acalypha.
© Unbel : In an umbel type.
of inflorescence, the rachis becomes
eondensed and stalked, Hlowers are
arranged on its Gp Like the spotes in
am umbrella, The flowers sre usually bracteata, Thos
the bracts form a whorl or a cluster at the bate of
Hower This group of bracts is called involucre eg,
Onioa,
(© Capitutum + In a capitolom type of
infloreiwence, the peduncle
‘becomes Hat and disk Hike, It is
called receptacle, Smell, scasile
flowers arc arrenged in #
centripetal order. Peripheral
flowers are called ray florets en!
central Hlowers are called disc
floret, The receptacle ia
surrounded by a who of bracts
known as an involucre c.g.
Sunflower, Tagetes, 20
(®) Cymose inflorescence : In this type of inflorescence, the apical
bud is tmnsformed into » flower. Thus, the development of inflorescence
axis becomes arrested. It may be divided into the following types:
(1) Cymaove solitary : In this type only ove pedicellete flower is borne
terminally by the pedunele. A joint some where in the stalk demarcates the
extent of peduncle and pedicel. e.g. Hibiscus, Argemone
@) Uniparous
(Momochosial) : The ruain axis ends
in a flower and the growth is contin-
ued by a single lateral branch. Tt may
be:
(A) Heticoid + I monocbasial
cyme, the apical bud gives rise to a
single lateral branch before being
‘transformed into # flower. The apical
io which the main axis ends io a flower after
producing rare than two branches e.g. Calotropis,
Red oleander
Coretta
Stigma
Aatber
Filament
Style
Calyx
‘Hamelin
‘bud of this branch also does the same. This
order continues. If the new branches are formed
sequentially on one side of the axis only. The
inflorescence is called unilateral, movochasial
cyme or belicoid. e.g. Hamelia
(®) Scorpio : Im this case the lateral
‘branches arise alternately on left and right sides
e.g. Heliotropium
@ Biparons (Dichasial ): A determinate inflorescence in which the
main axis ends in a flower after
producing two daugbter axis in
flowers. €.g. Jasmine, Nyctanthus
(®) Multiparous (olycha-
ial) : A determinate inflorescence
‘Flower : The flower is
the reproductive unit in the
angiosperms. It is meant for ME
sexual reproduction. It cousists
of a middle axis, called as
Floral axis. The expanded and swollen tip of the floral axis is called a
thalamus or receptacle while stalk like lower portion is called Pedicel
A typical flower consists of four wborls — cslyx, corolls, androecium
and gynoecium. The coropaneots of all these whorls are concentrically
arranged on thalamus. The calyx and corolla are accessory organs,
‘while androccium and gynoecium are reproductive organs. (@) Calyx : The calyx is the outermost whorl of the flower and its individual unit is
called sepal. Sepals are green, leaf-like and protect the flower in the bud stage. If the sepals
are free from one another, the calyx is called polysepalous and if they are united through their
‘margins to form a tube-like structure, the calyx is called gamosepalous
QO
Polysepalous Gamosepalous
(2) Corolla : The next whorl is of corolla.
Corolla is composed of petals. Petals are of various
shapes and colors. Corolla may be tubular, bell-
shaped, funnel-shaped, wheel-shaped or butterfly-
shaped. Petals are usually brightly colored to attract,
insects for pollination, They protect the floral whorls
arranged on their inside. They can also be of
Polypetalous —-Gamopetalous._polypetalous and gamopetalous types.
Sometimes, both these whorls appear similar, then, jointly they are called perianth,
eg. Crinum, Bougainvillea
Aestivation
Aestivation is the arrangements of sepals or petals in the bud condition of a flower.
It may be of the following types.
(A) Valvate = If the sepals and petals touch only along their margins and do not overlap
‘one another, then the aestivation is called valvate. e.g. Calotropis, Mustard
(B) Twisted : If the component members have their one margin overlapped by the
‘margin of another component, and the other margin overlapping the margin of another
component, the aestivation is called twisted. e.g. China Rose, Cotton
VIV90
OOOO
rN @ c
‘Types of Acstivation
A Valvate B - Twisted C - Imbricate D - Quincuncial E ~ Vexillary
21 (© Imbricate : One member is completely outside and one member is completely
inside. While other three members have one end outer and another one inner. This aestivation
is called imbricate. e.g. Cassia, Delonix (Gulmoher).
©) Quincuncial : It is a special type of imbricate aestivation where there are five
components, two components are outer, two are inner and in one component one margin is
‘inner and another margin is outer. e.g. Cucurbita, Melia
(©) Vexillary : This type of aestivation is seen in Nowers having vexillary corolla.
Out of the five petals, the largest (standard) overlaps the two Jateral petals (alae) which in
tum overlap the two smallest anterior petals (keel). This type of aestivation is known as
vexillary. e.g. Pea and Bean
(B) Androecium : This whorl which is arranged inner to corolla is made up of stamens.
Each stamen is made up of a filament, connective
and anther. Pollen grains are produced within anther.
Pollen grains can be smooth or spiny and of various
shapes. A sterile stamen is called staminode. The —
mature anther is bilobed, hollow and sac-like.
Anthers dehisce in various ways and liberate the
pollen grains. The filament and the anther are joined iaeel
Ptament
aww al
through a connective, This union can be of various
types.
on ea
‘The oumber of stamens varies. If all A Venu view, B - Dorsal
stamens are free from one another, they are called Se eee
free. If all stamens are jointly through their Drea
filaments, they are called monodelphous e.g. China
Rose. Sometimes, two groups are formed. They are
called diadelpbous. e.g. pea or when they ate in
more than two bundles, they are called polydelpbous
eg. Citrus
(@ Gynoccium : This whorl is arranged on
the innermost side and it is made up of carpels.
ach carpel possesses, at its base a hollow bag like
ovary, from its tip a tubular style occurs. The tip of
the style is called stigma and is the receptive surface
for pollen grains. Each ovary bears one or
moore ovules attached to a flattened cushion-like
placenta.
If a singal carpel occurs in the gyno-
cium it is called monocarpellary. e.g. Pea. If
more carpels occur, itis called polycarpellary. In
a polycarpellary gynoecium, if all carpels remains
free from one another it is called apocarpous.
eg. Rose, Lotus. If all carpel's are united with
fone another, itis called syncarpous, In such case
only one ovary occurs. e.g. Datura, Hibiscus
Cohesion of stamens Placentaion : The region from where an ovule develops inside the ovary is called
placenta.
is of the
@
®)
©
@)
®
‘The arrangement of ovules within an ovary is called placentation. The placentation
following types.
‘Marginal : In marginal placentation, the ovary is unilocular and the ovules are
ome on the inner folds of the ovary wall c.g. Pea, Bean
Parietal : In parietal placentation, the ovules develop on the inner wall in the
periphery of the ovary . Ovary is one chambered but it becomes two cham-
bbered due to the formation of the false septum e.g, Mustard and Argemone
Aczile : In axile placentation, ovules are arranged on a central axis in the ovary.
‘The ovary is divided into locules. The number of these locules is based on the
number of carpels e.g. Tomato, Hibiscus
Free contral : In free central placentation the ovules are bome on a central
‘axis, which arises from the base of the ovary and is not connected by partitions
with the wall of the ovary e.g, Dianthus
Basal ; If a placenta develop at the base of the ovary-chamber and bears
‘a single ovule, the placentation is called basal placentation e.g. Sunflower
Ovules Overy wall
Placeaam,
w
®
23 24
‘Zygomorphic
‘Types of Flowers
‘Types of Flowers : Types of flowers can
bbe described from various view points.
If all four whorls are present in a flower,
it is called a complete flower. But if any one of
the whorls is absent, then it is called an
incomplete flower.
‘When a flower has both androecium and
gynoecium, the flower is called bisexual. A
flower having cither stamens (male flower) or
carpels (female flower) is called unisexual
flower.
In symmetry, If a flower can be
divided into equal halves along any longitudinal
plane then it is called actinomorphic (radial
symmetry) e.g. Hibiscus, Datura, If it can
be so divided in one plane only then it is called
zygomorphic (bilateral symmetry). e.g. Bean,
Caesalpinia
A flower is called isomerous, when the
‘number of component members in all whorls
are the same. A isomerous flower may be trimerous, tetramerous or pentamerous,
when the floral appendages are in multiple of 3, 4, of 5 respectively, Flowers can also be
heteromerous
‘Tetramerous flower
‘The leaf, from the axis of which a flower develops is called a bract. The flower with
fa bract is called bracteate flower. Ebracteate flower lacks a bract. ‘Three kinds of Flowera occut on the basis of the position of the ovary. In a hypogynous
‘lower, the thalmmas becomes conical 0 fhrt the ovary occupies the highest. position, Such
‘an ovary is called superioe. e.g, Mustard, China rose end Deture. In a perigynous flower, the
‘thalams becomes flat, disc-lks. The ovary placed in the centre ia senai-inferior. Other floral
whorls sme arranged on ths rim of the thalamar. eg. Roes, Camalpinis. In x Epigynou
‘owes, the thalamus eavelops the ovary. Here, the over is inferion The other three whois
are arranged above the ovary c.g. Sunflower, Cocunaber
GBoperier ovary) Gent tafertoe amez) Gntinior ovary)
(Position of ovary « kinds cf flowers)
‘Frruit : The frait is defined as fortitized and sipened ovary. If fruit is formed without
Fertilization of ths ovary, itis called parthenocurpic fruit. Generally, the frit consists of a wall
‘or pericarp and seeds, The seeds are covered by « periemp in w fruit. The periemrp may be
dey or Hlesby. A trult whlch develops only trom en ovary is called trac fruit. Ia some casea
frait develope from the thalamus of some other parta of the flowers. Such type of fruit ia
colled fulse fnuit, In wpple, the thidlnmns 3s involved end in cashew nut fruit, the peduncle is
involved, those are false fruits,
‘Kinde of fruits : Based on thair ocigin and development, three Kinds of fruits occur —
simple, aggpogeio ened composite.
(A) Stumps fruit + Simaple fruit develops from monocarpellary ovary or nanlticarpellary
syncerpou ovary. It may be dry or fleahy. In dry simple frult the pericarp is dry. Simple fruita
are af two typos ~ dehiscent and indecent.
‘Dry Deslocont Fruit : When fruits ripen, their fruit walls debisce in various ways and
berate the scods. According to kind of dehiscence, they are classified into: follicies, legumea
‘and capeuloa. The follies type of fruit debisces by ono autare oaly. ¢.g. Calatrapis, Vinca.
‘The legume fruit dehisces slong two moture, eg, Poa, Benn, The capsule dehisces slong
‘mom then two sures. 6g. Cotton, Datura, In siliqus fruit dehiscence seats from lower part
‘ond proceeds upward by de subarea. o.g. Mustard. 26
‘Cotton
Indehiscent dry fruit : Tbe wall of the ripened fruit does vot dehisce. The pericarp
decomposes in a natural way and releases the seeds. They develop from monocarpellary to
polycarpellary syncarpous with one chamber and one ovule. Caryopsis, Achene, Cypsela Nut,
Samara are the types of indchiscent fruit, In caryopsis the pericarp and the seed coat are
fused and form a ‘bull’, There is a single sted in the fruit. e.g. Maize, Wheat. In achene
fruit pericarp and seedcoat are free from one another. ¢.g. Naravelia, Ocimum. In nut fruit,
the pericarp is very hard and stony. e.g. Cashewnut, Trapa. In eypsela fruit, the pericarp and
the seed coat remain free from each other. ¢.g, Tridar, Vernonia. In this fruit persistent
hairy calyx are found at the apex of the fruit. In samara, the pericarp became flat like
wings. e.g. Holoptelea, Hiptage.
Fleshy Fruit : In flesby fruits, pericarp is succulent and fleshy. They may be of three
types, drupe, berry and pome.
(@) Drupe + In drupe frnit, the pericarp is differeotiated into three regions, outer thin
and skinny epicarp, middle succulent or juicy mesocarp and an inner hard stony endocarp
which encloses a seed, e.g. Mango, Coconut
@e <
(2) Berry : In berry, epicarp and mesocarp arc similar to those scen in drupe fruit
but the endocarp is fleshy. e.g. Tomato, Orange.
Oe 27
(@) Pome : The fruit is false as it is surrounded by the fleshy thalamus.
Itis an edible part. True fruit remains inside the swollen thalamus. The ovary
enclosing seeds forms the central core of the fruit. ©.g. Apple.
(B) Ageregate Fruit : This fruit develops from an apocarpous,
polycarpellary gynoecium. Each carpel forms a fruitlet and thus, a cluster of
fruitlets known as etaerios develops from one flower. On the basis of the
kinds of the fruitlets, the aggregate fruits are named. Their chief types are as
follows.
(2) Etaerio of berries - e.g, Custard Apple.
(2) Etaerio of follicles - e.g. Calotropis.
() Btacrio of drupes - e.g. Raspberry
‘Custard Apple ‘Calotropis
(© Composite Fruits : A composite fruit develops from all the flowers of a whole
inflorescence forming one body at maturity. There are two types of multiple fruits namely
te
Ficus (Fig fruit)
Sits it pomgpi, ta avast pe tench ince
flowers along with bracts unite together into fleshy compound fruit. Flowers are usually sterile
and seeds are rarely formed,
Syoomus : It is derived from a special type of inflorescence known as hypanthodium,
which has a fleshy receptacle. It has large number of unisexual flowers. On ripening, the
receptacle becomes fleshy and juicy and forms the edible portion. e.g. Banyan fruit or Fig fruit.
Seed : The fertilized ovule is called a seed. A seed contains seed coat and embryo.
Embryo possesses cotyledons, plumule and radicle. The plumule is responsible for development
of shoot system and the radicle is responsible for development of root system. Food may be
stored either in the cotyledons or in a separate region. Such a region is called endosperm,
which is formed as a result of double fertilization. On the basis of the number of cotyledons, there
are two types of seeds - Dicotyledonous and
‘Monocotyledonaus. If tw cotyledons occur, the seed
is called dicotyledonous seed. e.g. Bean, Gram. If
a single cotyledon occurs, the seed is called
monocotyledonous sced e.g. Maize, Wheat. I the food is
sored in a seperate endosperm region, the seed is called
Endospermic seed ¢.g. Maize, Castor. If the food is stored in cotyledons and a region called
endosperm does not occur, the seed is called Non-endospermic seed e.g. Bean, Pea, Gram.
Structure of a Dicotyledonous Seed : Bean is a typical example of dicotyledonous
seod. The bean seed is flat kidney-shaped and yellowish white in colour. A seed coat occurs
(on the outside. ‘The seed coat has two layers. The outer one is tough and yellowish is called
testa and inner one is thin and wangpaceat. It is called tegmen. The hilum is a scar on the
seed coat through which the developing needs were attached 10 the fruit. Above the hilum
is @ small pore called the micropyle.
In the structure of the
embryo, two large, fleshy and aoe
white cotyledons found attached anise (ay \
to the embryonic axis, They anc Plmale [4 Biypocoty
often full of reserve food ~ Raaidle 1) J
‘materials, Plumnle occurs at one U3 = Cartedone
end of thie axis and radicle
‘occurs at the other end, Phumule
is protected by two minute
leaves. During germination it develops into the shoot while due to growth and development,
the primary tap root system is organized from radicle, The region of embryonic axis between
‘plumule and cotyledons is called epicotyl and that between radicle and cotyledons is called
hhypocoryl. Bean seed is dicotyledonous, noneadospermic seed.
Structure of Momosotyledonous socd : Maize is a typical example of monocotyledon
seed. Maize grain is flat, yellow, narrow at one end and broad at the other end. Tf the seed
is cut longitudinally into two parts and the cut face stained with iodine, the endosperm part
(deep blue because of starch)
and the embryo part
(yellowish) can be easily
demarcated. Usually the
‘embryonic region is located in
the narrow flat region. The
remaining part is the
endospermic region. The
stcuctre of maize grain can
be studied in its longitudinal
section. ‘On the outermost side a hull occurs. It is a tough covering formed through fusion of
pericarp and seed coat. An aleurone layer occurs under the hull. This is made up of big
‘square or rectangular cells. Grains of proteins are stored in these cells.
A single, thin and shield-shaped cotyledon occurs in the embryonic region. It is
called scutellum, The outer layer of scutellum which remains in contact with endosperm
is called epithelial layer. The endospermic region is large. It stores food mainly in the
form of starch.
At the narrow end of scutellum, the embryonic axis remains attached. At one end of
this axis, occurs plumule and its protective covering is called coleoptile. At the other end of
this axis, occurs radicle and its protective covering is called coleorhiza.
‘The maize grain is a representative of monocotyledonous, endospermic seed.
Floral Formula : Before the construction of floral diagram and floral formula, various
morphological features are used to describe a flowering plant. Such a description has to be
brief, in a simple and scientific language and presented in a proper sequence.
First of all, there should be a mention of the habitat of the plant. ‘Then the plant is
described beginning with its habit, vegetative characters- stem, leaves and then inflorescence,
floral characters and floral parts. After describing various parts of a plant, a floral diagram
and a floral formula can be structured,
In construction of the floral formula, the number of members in the floral whorls, their
‘union with one another, their insertion on thalamus, their association with other whorls, etc.
are taken into account. Various symbols used in a floral formula and their meanings can be
explained as under :
1. Bracts 2. Symmetry
Br = Bracteate © = Actinomorphic or Regular flower
Bbr = Ebracteate (Dor % = Zygomorphic or irregular flower
Brl = Bracteolate
3 Sex 4. Calyx
OS = Stamina flower K = Calyx
Q_ = Pistillate flower K, = Four free sepals
K 4 = Four fused sepals
5. 6. Perianth
P= Perianth
C, = Four free petals P, = Six free tepals
Cy = Four fused petals Pig = Six fused tepals
Pay =
ix tepals in two whorls of
three each
29 30
Ja constructing the formula, after the symbol of concemed floral whorl, the number of
amambers in thet whorl is writiee, Ths following floral formule and floral diggram in Sgure
represent the Mustard plant :
Floral formula of Mustard plant : @ Cs Kg Cy Anu Seay
@ Mote ais Floral diagram ; A Floral diagram provides information about the number of parts of
a flower, their arrangement, their adhesion and cohesion with other whorl and their relation
to the mother axis. The position of the mother axis with respect to the flower is represented
by a dot on the top of the floral diagram. On the outermost side calyx is shown. Then
sequentially, inside, corolla, androecium and gynoecium are shown. If possible placentation is
also shown, Extrose anthers are to be faced toward the petals and the introse ones towards
the gynoccium. Staminodes are represented either by a cross (x) or asterisk (*). If a bract
is present, it is shown under the floral diagram.
Description of families
‘To understand the method of discription of flowering plants, we shall discribe families
an illustration, discription of three family is given.
Fabaceae
Classification : Class = Dicotyledons
Subclass — -—_-~Polypetalae
Series ~ — Caliciflorae
Order — Rosales
Family - Fabaceae
‘This family was earlier called Papilonoideae, a sub-family of family Leguminosae.
‘Vegetative characters :
Habitat : It is distributed all over the world.
Habit : Mostly trees, shrubs and herbs. Some of them are climbers. Root is with root
nodules. Often spiny outgrowth present on stem.
Leaf : Pinnately compound or simple, alternate, leaf base pulinate, stipulate stipules
spiny, venation reticulate.
Floral characters : Inflorescence racemose.
Flower : Complete, zygomorphic, bisexual, pedicellate, bracteate, hypogynous
Calyx
Corolla : Petals five, coloured variously, polypetalous, papillionaceous, consisting of one
posterior standard, two lateral wings and two anterior ones forming a keel (enclosing stamens
and pistil ), vexillary aestivation.
Androeelum : Ten, diadelphous ( (9}+1) anther dithecous.
Sepal five gamosepalous, imbricate aestivation.
Gynoecium : Monocarpellary, ovary superior, unilocular with many ovules, style single
with capitate stigma, marginal placentation.
Fruit : Legume, seed one to many, non-endospermic.
Floral formula : Br, ©, Qs Ky) Cryzse) Arvo) G
31 32
‘Androecium and
‘Gynocdum
‘TS. of Ovary Floral Diagram
Fabaceae : Lathyrus aphaca (Pea)
Scientific name
(1) Phaseolus mungo
Q) Cajanus cajan
8) Cicer arietinum
(4) Deris indica
Economic importance
Many plants belonging to this family are the sources of pulses (Black gram, Green gram,
Bean, Pea, Lentil) edible oil (Groundnut, Soyabean), dyes ( Indigofera ), fibres (Sun hemp),
fodder (Crotolaria, Sesbania ) and medicines ( Muliathi).
Solanaceae
Classification :
Class Dicotyledons
Subclass — Gamopetalae
Series — Bicarpellatae
Order Polymoniales
Family ~ Solanaceae
(Green gram)
(Pegion pea)
(Chana)
(Karanja) It is a large family, normally called as the potato family.
‘Stamen Gynoccium T:S. of ovary Floral Diagram
Solanaceae : Solanum nigrum (Piludi)
Vegetative Characters
‘Habitat : It is widely distributed in tropical and temperate regions.
Habit : Plants mostly herb, rarely climber, shrubs and small tres.
Stem : herbaceous, aerial, cylindrical, hairy, underground stem in potato.
Leaf : Simple, alternate, hairy, exstipulate, pinnately dissected, Venation reticulate,
Floral characters
Inflorescence + Solitary cyme or monochasial, helicold cyme, apical or axillary.
Flower : Complete, actinomorphie, bisexual, hypogynous.
Calyx : Sepals five, gamosepalous, tubular, valvate, persistent.
Corolla : Petals five, gamopetalous, valvate, variously shaped.
Anidroecium : Stamens five, epipetalous, introse.
Gynoecium : Bicarpellary, Syncarpous, ovary superior, many ovules in each locule,
Placentation axile.
Fruit : Capsule or berry, seed endospermic.
Floral formula : Ebr, @, G. Kis) Cy As Gay
33 a
@
@
a
Scientific name
Datura fasuosa
Solanum melongena
Solanum tuberosum
Solanum nigrum
Economie importance
‘Many plants belonging to this family are the sources of food (Potato, Tomato, Brinjal),
‘medicines (Ashwagandha) and spices (Chill). Many plants are omamental (Petunia).
(Datura)
(Brinjal)
(Potato)
(Piludi)
Liliaceae
Classification :
Class — — Monocotyledons
Series. - Coronariae
Family — Liliaceae
‘Commonly called the lily family. Vegetative characters :
K It is distributed in the major parts of the world
bit : Mostly herbaceous, some are climbers (Asparagus) some are xerophyles (Agave).
‘Vegetative reproduction mainly by bulb and rhizome.
Leaf ; Simple altemate, opposite or whoried, exstipulate, mostly basal, venation parallel
paracters :
Inflorescence : Solitary, axillary, cymose often umbellate clusters.
ver : Complete actinomorphic, bisexual, bracteate, hypogynous.
anth : Perianth sepaloid or petaloid ( 343), free, valvate, aestivation.
ium + Stamen six (343), free or periphyllous, filament long, introse or extrose.
Fi
A
Gynaccium : Tricarpellary, syncarpus, ovary superior, trilocular with many ovules, axile
placentation,
uit : Capsule rarely berry, seed endospermic,
Floral formula : Br, @. C, Pars Ases Goy
Scientific name
(1) Altium cepa (Onion)
(2) Aloe vera (Kunwarpathu)
(3) Asparagus racemosus (Satavari)
(4) Gloriosa superba (Vachhnag)
‘onomic importance :
Many plants belonging to the family are good sources of medicines e.g. Aloe and
Asparagus. Many plants are ornamental (Tulip).
‘Summary
When the young plants grow and the vegetative parts mature, flowers make their
appearance. The arrangement of flowers on the rachis is called inflorescence. There are two
‘main types of inflorescence ~ racemose and cymose. The flowers are arranged in different
types of inflorescence. A typical flower consists of four whotls — calyx, corolla, androecium
and gynoecium. The arrangement of sepals or petals in the bud condition of the flower is
called aestivation. The main types of aestivations are valvate, twisted, imbricate, quincuncial
and vexillary. Androecium is composed of stamens. Stamens of flowers may be free or
united with other members such as petals or among themselves. Gynoecium is the inner most
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. When more than one carpel is present,
they may be free of fused. The arrangement of ovules within the ovary is called placentation.
‘The placentations are of different types namely marginal, axile, parietal, basal and free
central. ‘Types of flowers can be described from the various points of view such as presence
of four whorls, presence of bracts and position of ovary in relation to other parts. After
fertilization, the ovary is converted into fruit and ovules into seeds. Based on origin and
development, three kinds of fruits occur ~ simple, aggregate and composite. Simple fruit may
35 Exercise
1, Put a dark colour in a given circle for correct answer :
(2) Which of the following plants shows spike inflorescence ?
(A) Mustard OQ ®) Caesalpinia O°
(©) Achyranthus OO ©) Mulbeny Oo
@) Onion is the example of which type of inflorescence ?
(A) Capitutum OO ®) Catkin fo)
(©) Spadix OQ @) Umbel Oo
eB) _ is the example of scorpioid type of inflorescence.
(A) Hametia O — ® Hetiotropium Oo
(C) Hibiscus © ©) Argemone O°
(4) The expanded and swollen tip of the pedicel is called
(A). Rachis OQ @® Thalamnus Oo
(©) Peduncle O ©) Receptacle Oo
(5) Which of the following are accessory floral organs ?
(A) Calyx and gynoecium ©) (B)_Androecium and Corolla ©
(©) Calyx and Corolla ©) (D)_Gynoecium and Corolla O°
(6) Of the following which is an example of perianth ?
(A) Hibiscus OQ — @®) Sunflower °O
(© Crinum O- ©) Datura oO
(7) Which of the following is an example of vexillary placentation ?
(A) Cassia OO ® Cotton oO
(©) Pea OO ©) Melia Oo
(8) OF the following which is an example of imbricate placentation ?
(A) Gulmoher Oo (B) Cucurbita Oo
(©) China Rose OO ©) Bean Oo
(9) What is tue for Sunflower ?
(A). Superior ovary © — ®)_Epigynous flower Oo
oO
(© Axial placentation ©) (D)_Umbel inflorescence 2.
(40) Semi-inferior ovary is observed in flower.
(A) Epigynous O — ®) Perigynous Oo
(C)_ Hypogynous O — @)_ None of above Oo
(11) Which of the following is called fertilized and ripened ovary ?
(A) Seed OO @) Owle fe)
(© Fruit O ©) Placenta Oo
(12) Maize is an example of ___ type of fruit.
(A) Cypsela O- ®) Achene fo}
(©) Caryopsis OQ @) Nut Oo
(13) Which of the following is an example of follicles fruit ?
(A). Calotropis O- ®) Cotton oO
(© Maize OO ® Ample O°
(04) Which type of the fruit is pineapple ?
(A) Capsule Oo (B) Etaerio of follicle Oo
(C) Composite Oo (D) Etaerio of berries Oo
as) is an example of endospermic seed.
(A) Gram OO ®) Pea Oo
(©) Bean O- ©® Maize Oo
(16) Which of the following is sign for bisexual flower ?
ag Oo o#@ O°
od oO M® Oo
an ‘is an example of family solanaceae.
(A) Karanja OB) Potato Oo
© Gram O- ©) Satavari Oo
Explain/Define the following terms :
Anthotaxy, Catkin, Spike, Involucre, Aestivation, Gamopetalous, Placentation, Actinomorphic
flower, Perianth, Hypogynous flower, Fruit, Seed, Caryopsis, Drupe,
State the example of the following :
‘Umbel inflorescene, Helicoid, monochasial cyme, Perianth, syncarpous carpel, Diadelphous,
Polypetalous, Hypogynous, Actinomorphic, Imbricate aestivation, Basal placentation, True
fruit, Caryopsis, Parthenocarpic fruit, Hull, Berry, Etaerio of berries,
Aggregate fruit, Non-endospermic seed, Liliaceae family, Solanaceae family
Write notes on :
(Q)_ Capitulum inflorescence (D_Indehiscent dry fruit
(2) Uniparous cyme inflorescence (8) Fleshy fruit,
@) Corolla (©) — Axgregate fruit
(@)—Aestivation (10) Embryonic region in dicot seed
() Gynoecium (1) Floral diagram
(©) Types of flower on the basis of position (12) _Placentation of ovary
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5.
%
10,
11.
a2
13,
14,
15.
16,
Distinguish between :
(2) Racemose inflorescence ~ Cymose Inflorescence
2) Uniparous inflorescence — Biparous Inflorescence
@) Hypogynous flower ~ Epigynous flower
(4) Regular flower — regular flower
(S) Androecium — Gynoecium
© Axile placentation — Parietal placentation
( Simple fruit ~ Fleshy fruit
(8) Simple fruit — Aggregate fruit
(9) Bean Seed — Maize Seed
(10)Papilionaceae — Liliaceae
Draw labeled diagram of :
() LS. of typical flower (2) Spadix inflorescence
(3) Vexillary aestivation ) LS. of dicot seed
(S) LS. of Monocot seed
What is inflorescence ? Describe Racemose types of inflorescence with figure.
Describe various types of flowers.
What is aestivation ? Describe various types of aestivation.
What is placentation ? Describe various types of placentation with figure.
Describe various types of fleshy fruits.
Describe structure of dicotyledonous seed.
Describe structure of Maize seed.
Give general character of Papilionaceae family. Give scientific names of two plants from
the family.
Give classification of Solanaceae family. Describe it with diagram of floral characters.
How is the floral diagram of family Liliaceae constructed ? Anatomy of Flowering Plants
‘The plant body is made up of cells. The cells are organized into tissues and in tum
‘various tissues are organized together and form tissue system. Tissue systems form organs.
Different organs in a plant show differences in their internal structures. Study of intemal
structure of plant is called plant anatomy. Within angiosperms, the monocots and dicots are
also seen to be anatomically different. In previous chapter we have studied external morphology
of plants. Now we shall study the intemal structure of plant organs.
The Tissue
A. tissue is a group of cells having a common origin and performing specific
functions. A plant is made up of different kinds of tissues. Plant tissues can be divided
mainly into two groups.
(1) Meristematic tissues (2) Permanent tissues
(1) Meristematic tissues : Meristematic tissues consist of actively dividing cells.
A group of actively dividing cells is known as meristem. Plants have different kinds of
‘meristems.
‘The meristems which are found at the tips of shoots and roots and produce primary
tissues are called apical meristems. These meristems are responsible for the linear growth
of the plants, During elongation of stem, some cells are left behind the apical meristem
of shoot and they constitute the axillary bud. Such buds are present in the axils of leaves
and are responsible for the formation of flower or a branch.
‘The meristem which is located in between permanent tissues is called intercalary
‘meristem. Such meristems occur in grasses and regenerate parts eaten up by the grazing
herbivores.
Both apical meristems and intercalary meristems are primary meristems because
they appear early in the life of plant and contribute to the formation of primary plant body.
‘The meristem that occurs in the mature regions of shoots and roots of many plants
‘and appear later than primary meristem is called secondary or lateral meristem. Lateral
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meristem usually occurs beneath the bark of the tree in the form of cork cambium and in
the vascular bundles of dicots in the form of vascular cambium, The activity of this meristem
results in the formation of secondary growth.
(2) Permanent tissues : Following divisions of the cells in both primary and secondary
‘meristems, the newly formed cells become structurally and functionally specialized and lose
the ability to divide. Such cells are known as permanent cells and constitute permanent
tissues. There are two types of permanent tissues : i) Simple permanent tissue and ii) Complex
permanent tissue.
Simple tissue consists of a single type of cell, while the complex tissue is formed of