Morphology of Angiosperm

▢ Introduction:

Table 1: Morphology Basics

Term / Point	Meaning
Morphology	Study of form, structure, size, colour, development and relative position of organism parts
Anthology	Study of flowering plants / flowers
Angiosperms	Flowering plants
Phanerogamic	Flowering / visible reproductive organs
Spermatophytic	Seed-bearing plants
Sporophytic	Main plant body diploid / 2n
First flowering plants	Appeared in Jurassic period

▢ Comparative Morphology:

Table 1: Root, Stem, Leaf, Inflorescence and Flower

Part	Arrangement	Stalk / Axis	Special term
Root	No node and internode	Root axis	Descending axis
Stem	Nodes and internodes present	Stem axis	Ascending axis
Leaf	Phyllotaxy = arrangement of mature leaves on stem/branches	Petiole	Prefoliation = arrangement of young leaves in bud
Inflorescence	Arrangement and distribution of flowers on shoot system	Peduncle	Anthotaxy = arrangement of flowers in inflorescence
Flower	Floral whorls on condensed axis	Pedicel	Thalamus / torus = swollen end of pedicel

▢ Phyllotaxy and Prefoliation:

❖ Phyllotaxy:

◉ Definition: Arrangement of mature leaves on stem or branches

Table 1: Types of Phyllotaxy

Type	Feature
Alternate / Spiral	Single leaf from each node
Opposite	Pair of leaves arise from node opposite to each other
Opposite superposed	Leaves of successive nodes in same plane → two rows
Opposite decussate	Opposite leaves of one node at right angle to adjacent node
Whorled / Verticillate	Three or more leaves from a single node

❖ Prefoliation:

◉ Definition: Arrangement of immature / young leaves in bud

Table 1: Prefoliation

Type	Meaning	Example
Ptyxis	Arrangement of individual immature leaf in bud	Circinate
Circinate ptyxis	Young leaf coiled like watch spring	Fern, Cycas, banana
Vernation	Arrangement of immature leaves with respect to each other in bud	Leaf bud
Aestivation	Arrangement of floral parts in floral bud	Sepals / petals

📚

ROOT

▢ Introduction:

Table 1: Root Characters

Feature	Point
Position	Usually underground
Colour	Non-green
Direction	Descending part of plant
Geotropism	Positively geotropic
Phototropism	Negatively phototropic
First structure in germination	Root / radicle
Main root	Primary root / tap root from radicle
Lateral roots	Arise from pericycle; endogenous
Adventitious root	Root from any part other than radicle
Tissue culture root	Arises from callus

❖ Apogeotropic Roots:

•
Coralloid roots of Cycas
•
Pneumatophores of mangrove plants

❖ Functions:

•
Fixation
•
Absorption
•
Conduction
•
Assimilation in some roots
•
Reproduction in some roots

❖ Absent in Root:

•
Nodes and internodes
•
Buds generally absent
•
Leaves
•
Flowers

▢ Special Plants:

Table 1: Plantless Roots and Rootless Plants

Category	Examples
Plantless roots	Podostemon, Arceuthobium, Rafflesia, Sapria, Monotropa
Rootless plants	Myriophyllum, Balanophora, Utricularia, Ceratophyllum, Cuscuta, Wolffia

📖

Tap root modifications

▢ Fleshy Tap Roots:

Table 1: Storage Tap Roots

Type	Shape	Example
Fusiform	Spindle-shaped; tapering at both ends	Raphanus sativus / radish
Napiform	Top-shaped; swollen base, abruptly tapering apex	Brassica rapa / turnip
Conical	Cone-shaped; broad base, tapering apex	Daucus carota / carrot
Tuberous	Irregular swelling	Mirabilis jalapa / four o'clock plant

▢ Other Tap Root Modifications:

Table 1: Tap Root Modifications

Type	Feature	Examples
Nodulated / tuberculated root	Root nodules in legumes; nitrogen fixation by Rhizobium; leghaemoglobin protects nitrogenase and supplies O₂	Leguminous plants
Pneumatophores / respiratory roots	Negatively geotropic roots with pneumatophores / breathing pores	Rhizophora, Avicennia
Buttress roots	Laterally compressed horizontal roots at base of trunk for support	Ficus religiosa, Ficus elastica, Bombax ceiba
Mycorrhizal roots	Root cap and root hairs absent; fungal hyphae cover root; phosphorus absorption	Pinus, Betula, orchids
Reproductive tap root	Develops adventitious buds for vegetative propagation	Dalbergia

❖ Pneumatothodes: Minute pores on exposed pneumatophores; anatomically and morphologically similar to lenticels

📖

Adventitious root modifications

▢ Fleshy Adventitious Roots:

Table 1: Storage Adventitious Roots

Type	Swelling	Examples
Annulated root	Ring-like swelling	Cephaelis, Psychotria / ipecac
Nodulose root	Swollen at tip	Curcuma amada / mango ginger, Curcuma domestica / turmeric
Moniliform / beaded root	Swelling at intervals	Momordica charantia / bitter gourd
Tuberous root / single root tuber	Single, no definite shape	Ipomoea batatas / sweet potato
Fasciculated root	Clustered roots with definite shape	Asparagus, Dahlia
Palmate root	Branched root like palm	Orchis

▢ Support and Special Adventitious Roots:

Table 1: Adventitious Root Modifications

Type	Feature	Examples
Pillar root / prop root	Arises from large branches; thick woody root; support + hygroscopic absorption; lenticels present	Ficus benghalensis, Rhizophora
Stilt root	Arises obliquely from lower nodes; supports plant	Sugarcane, maize, screw pine
Climbing / clinging root	Adventitious roots from node/internode for fixation	Pothos, Piper betle, ivy, vanilla, orchid
Epiphytic root	Clinging root for fixation; hygroscopic root with velamen absorbs moisture	Orchids
Haustorial / parasitic / sucking root	Absorbs nutrition from host	Cuscuta, Viscum
Photosynthetic / assimilatory root	Green roots perform photosynthesis	Trapa, Tinospora, Taeniophyllum
Floating root	Leafy floating roots for balance	Pistia, Eichhornia, Jussiaea
Root thorns	Roots arise from stem and become protective thorns	Pothos, Acanthorhiza
Reproductive root	Adventitious roots produce buds	Dahlia, sweet potato, Trichosanthes dioica
Haptera	Root-like structure from leaf margin; attaches plant to substratum	Podostemon
Contractile root	Arises from underground stem; pulls organ into soil	Crocus, onion, Freesia
Leaf root / foliar root / epiphyllous root	Leaf modified into root for balancing	Salvinia
Nest root	Adventitious roots forming nest-like structure	Dischidia

📚

STEM

▢ Introduction:

Table 1: Stem Characters

Feature	Point
Direction	Ascending part of plant
Origin	Plumule of embryo
Hair	Stem hairs commonly multicellular
Differentiation	Nodes and internodes present
Branches	Produced exogenously from surface meristem in cortex
Structures borne	Branches, leaves, flowers

▢ Aerial Erect Stem:

Table 1: Aerial Erect Stem Types

Type	Feature	Examples
Culm	Distinct nodes and internodes; internode hollow or spongy; node solid	Grass family, sugarcane, maize
Excurrent	Extreme apical dominance; lower branches longer than upper	Most conifers
Deliquescent	Dome / umbrella-shaped crown; branches grow equally in all directions	Mango, peepal
Pseudostem	Aerial unbranched trunk-like structure formed by compact leaf sheaths; true stem underground rhizome	Banana, onion, ginger
Caudex	Unbranched main trunk with tuft of leaves at crown; trunk marked by leaf scars	Phoenix, coconut, Carica, Cycas

▢ Aerial Weak Stem:

❖ Twiners vs Climbers:

Table 1: Twiners vs Climbers

Type	Feature	Examples
Twiner	Main stem coils around support; no special attachment organ; coiling direction genetically determined	Bean, Convolvulus, Clitoria, Dioscorea
Climber	Uses accessory organs for climbing	Root climbers, tendril climbers, scramblers
Sinistrose twiner	Left-handed / anticlockwise coiling	—
Dextrose twiner	Right-handed / clockwise coiling	—

❖ Climbers:

Table 1: Types of Climbers

Type	Modification	Examples
Root climber	Adventitious roots for climbing	Pothos, Piper, betel
Stem tendril climber	Axillary bud → Passiflora; extra-axillary bud → Cucurbita; branch tip → grape	Passiflora, Cucurbita, Vitis vinifera
Leaf tendril climber	Whole leaf / leaflet / leaf tip / petiole / stipule modified	Lathyrus aphaca, pea, sweet pea, Gloriosa, Nepenthes, Smilax
Scrambler / rambler	Uses hooks / pointed structures for climbing	Stragglers

◉ Haptotropism: Coiling of tendril around support due to contact

❖ Thorns, Spines and Prickles:

Table 1: Thorn vs Spine vs Prickle

Structure	Modification / Origin	Examples
Thorn	Modified stem / axillary bud	Duranta, Bougainvillea, citrus
Spine	Modified leaf; bud present in axil	Aloe vera, Opuntia, Asparagus
Prickle	Superficial outgrowth; may arise from any plant part	Climbing rose

❖ Lianas:

•
Large woody climbers and twiners of tropical rain forests
•
Gnetum
•
Bauhinia
•
Bignonia
•
Hiptage

▢ Sub-aerial Stem:

❖ Introduction:

•
Prostrate weak stem modification
•
Produced for vegetative propagation
•
Arises from axil of lower leaves

❖ Types:

Table 1: Sub-aerial Stem Modifications

Type	Feature	Examples
Trailer	Stem spreads horizontally without adventitious roots; fixed at one point by tap root; no daughter plants	Convolvulus, Oxalis, Portulaca, Tridax, Euphorbia prostrata
Runner	Horizontal stem with adventitious roots at nodes/internodes	Oxalis, Cynodon, Lippia, grasses, Centella
Offset	One-internode long, thick, short runner	Pistia, Eichhornia, Agave
Sucker	Obliquely growing running stem	Banana, chrysanthemum, mint
Stolon	Slender lateral branch; on touching soil forms leaves above and roots below	Strawberry, jasmine, blackberry
Sobole	Underground running stem	—

❖ Trailer Types:

Table 1: Trailers

Type	Feature	Examples
Procumbent	Flat branch on ground	Convolvulus, Oxalis
Decumbent	Initially vertical then lies on ground	Portulaca, Tridax
Diffused	Branches spread in all directions	Euphorbia prostrata

▢ Underground Stem:

❖ Introduction:

•
Subterranean stem
•
Plants with underground stem = acaulescent
•
Storage and perennation
•
Vegetative propagation common

Table 1: Underground Stem Modifications

Type	Feature	Examples
Bulb	Condensed disc-like stem with fleshy leaf bases; adventitious roots below	Onion, garlic, lily
Corm	Underground vertical, spherical/globular, unbranched stem; cataphylls; circular nodes	Colocasia, Amorphophallus, Colchicum autumnale
Rhizome	Reduced food-storing stem with cataphylls, nodes, internodes, adventitious roots; diageotropic	Banana, ginger, turmeric, canna
Tuber	Swollen underground branch from axil of lower leaf; nodes arranged spirally; eyes present	Potato

❖ Bulb Types:

Table 1: Bulb Types

Type	Feature	Example
Tunicated bulb	Covered by tunic	Onion, garlic
Scaly / loose bulb	Tunic absent	Lily

❖ Tuber Eye: Each eye of potato has 3 buds → 1 axillary + 2 accessory buds

❖ Largest Corm: Amorphophallus

▢ Stem Modifications:

Table 1: Special Stem Modifications

Type	Feature	Examples
Phylloclade	Green, photosynthetic, succulent stem of indefinite growth leaves caducous xerophytic adaptation	Opuntia Euphorbia Muehlenbeckia Casuarina
Cladode / Cladophyll	Photosynthetic stem of definite growth usually one/two internodes long	Asparagus Ruscus Lemna
Thalamus	Condensed axis of flower; edible part of apple	Apple

❖ Mnemonic:

•
Phylloclade → POEM
•
Cladode → CAR

📚

LEAF

▢ Introduction:

Table 1: Leaf Characters

Feature	Point
Definition	Green, exogenous, lateral outgrowth borne on node of stem/branch
Growth	Limited; by intercalary meristem
Major functions	Photosynthesis, gaseous exchange, transpiration
Prophyll	First leaf of plant from shoot meristem as leaf primordium
Phyllome	All types of leaves present in a plant
Single-leaf plant	Monophyllaea
Two-leaf plant	Welwitschia
Absorbing leaf	Lamina of insectivorous plant
Dicot leaf	Dorsiventral + horizontal
Monocot leaf	Isobilateral + vertical

❖ Leaf Surfaces:

Table 1: Leaf Surfaces

Surface	Synonym	Direction
Abaxial surface	Dorsal / lower surface	Away from stem axis
Adaxial surface	Ventral / upper surface	Toward stem axis

📖

Leaf classification

▢ Based on Insertion:

Table 1: Leaf Types by Insertion

Type	Feature	Examples
Radical	Leaves arise above root system from condensed shoot; internodes short	Radish, carrot, turnip
Cauline	Leaves borne on main stem / inflorescence stalk	Mustard, maize, sugarcane
Ramal	Leaves on nodes of stem branches	Mango, peepal

▢ Based on Life Span:

Table 1: Leaf Types by Life Span

Type	Feature	Examples
Caducous	Fall soon after appearance	Opuntia
Deciduous	Fall simultaneously at end of growing season	Acacia catechu, Dalbergia sissoo, mulberry, Populus
Persistent	Live more than one season	Evergreen trees, Pinus, Ficus, mango

▢ Based on Origin and Function:

Table 1: Leaf Types by Origin and Function

Type	Feature	Examples
Foliage leaf	Normal green photosynthetic leaf	Most plants
Reproductive leaf	Produces adventitious roots/shoots for regeneration	Begonia, Bryophyllum
Cotyledonary leaf	Derived from cotyledon; stores food and nourishes seedling	Cucumber, tamarind, castor, bean
Sporophyll	Spore-bearing leaf	Fern frond
Trophophyll	Vegetative / non-spore-bearing leaf	—
Cataphyll	Protective leaf on underground stem	Rhizome, corm
Scale leaf	Reduced leaf found in cladode	Pinus
Hypsophyll / Bract	Protects floral bud	Bracts

📖

Parts of leaf

Table 1: Leaf Parts

Part	Synonym	Feature
Leaf base	Hypopodium	Basal part of leaf
Petiole	Mesopodium / leaf stalk	Develops last in leaf
Lamina	Epipodium / leaf blade	Supported by midrib, veins and veinlets

▢ Leaf Base:

•
Pulvinous → swollen leaf base
•
Sheathing leaf base → expanded base covering stem partially/completely; common in monocots, grasses, wheat, sugarcane, maize

▢ Petiole Types:

Table 1: Petiole Modifications

Type	Feature	Examples
Winged petiole	Petiole with wing-like expansion	Citrus, sweet pea
Tendrillar petiole	Petiole modified into tendril	Nepenthes, Clematis
Bulbous petiole	Spongy, inflated, aerenchymatous	Eichhornia
Phyllode	Green flattened leaf-like structure from petiole	Australian acacia, Parkinsonia

▢ Other Structures:

•
Stipules → at base of leaf
•
Stipels → at base of leaflets

📖

Venation

▢ Definition: Arrangement of veins and veinlets in lamina

Table 1: Types of Venation

Type	Common in	Subtypes / Exceptions
Reticulate venation	Dicots	Pinnate/unicostate; palmate/multicostate → convergent/divergent
Parallel venation	Monocots	Pinnate/unicostate; palmate/multicostate → convergent/divergent
Furcate venation	Forked venation	—

▢ Reticulate Venation Exceptions in Dicots:

•
Calophyllum
•
Corymbium
•
Eryngium

▢ Parallel Venation Exceptions in Monocots:

•
Alocasia
•
Arisaema
•
Colocasia
•
Dioscorea
•
Smilax

📖

Types of leaves

Table 1: Simple and Compound Leaves

Type	Subtypes
Simple leaf	Single lamina
Pinnately compound leaf	Unipinnate, bipinnate, tripinnate, decompound
Palmately compound leaf	Unifoliate, bifoliate, trifoliate, quadrifoliate, multifoliate/digitate

📚

INFLORESCENCE

▢ Introduction:

❖ Definition: Arrangement and mode of distribution of flowers on shoot system

❖ Purpose: Maximum pollination

❖ Anthotaxy: Arrangement of flowers in inflorescence

▢ Solitary Inflorescence:

Table 1: Solitary Flowers

Type	Feature	Example
Solitary terminal	Single flower at tip	Papaver somniferum / poppy
Solitary axillary	Single flower in leaf axil	Hibiscus rosa-sinensis / China rose

▢ Racemose vs Cymose:

Table 1: Racemose vs Cymose Inflorescence

Feature	Racemose	Cymose

Growth	Indefinite / indeterminate / continuous	Definite / determinate / discontinuous
Peduncle	Does not end in flower	Ends in flower
Arrangement	Acropetal / centripetal	Basipetal / centrifugal
Flower age	Older at base, younger at apex	Older at top/centre, younger at base/periphery

▢ Simple Racemose:

Table 1: Simple Racemose Inflorescences

Type	Feature	Examples
Typical raceme	Unbranched peduncle with stalked/pedicellate flowers	Radish
Corymb	Lower flowers long stalked, upper flowers short stalked; all flowers at same level	Iberis amara / candytuft
Corymbose raceme	Mixture of raceme and corymb	Mustard
Spike	Sessile flowers in acropetal succession; most common type	Bottle brush / Callistemon
Catkin / Amentum	Unisexual, sessile, often hanging spike	Jackfruit, pineapple, mulberry, Salix, Betula
Umbel	Flowers arise from same point with equal pedicels; reduced peduncle; involucre present	Umbellifers
Head / Capitulum	Flattened peduncle forms receptacle with sessile florets; ray florets peripheral, disc florets central	Marigold, sunflower, chrysanthemum
Spadix	Thick fleshy peduncle; covered by spathe; male flowers top, neuter middle, female base	Colocasia, Arisaema, female maize

❖ Involucre Found In:

•
Capitulum
•
Cyathium
•
Umbel

▢ Compound Racemose:

Table 1: Compound Racemose Inflorescences

Type	Feature	Examples
Panicle / compound raceme	Branched raceme	Cassia fistula, male maize
Compound corymb	Formed by small corymbs	Cauliflower
Compound umbel	Umbel of umbels	Coriander
Spikelets	Spike of spikes	Graminae, Amaranthus
Compound spadix	Branched spadix	Palm, coconut, banana

❖ Notes:

•
Bracts of main corymb = involucre
•
Bracts of small corymb = involucels
•
In banana, whole inflorescence covered by spathe

▢ Cymose Inflorescence:

Table 1: Cymose Types

Type	Feature	Examples
Monochasial / uniparous cyme	Terminal branch ends in one flower and pushes one lateral branch	Helicoid, scorpoid
Helicoid cyme	Flowers borne on one side	Begonia, Drosera, Heliotropium
Scorpoid cyme	Flowers alternately on both sides; zig-zag axis	Freesia, Ranunculus, cotton
Rhipidium	Scorpoid cyme with all flowers in one plane	Solanum nigrum
Dichasial / biparous cyme	Terminal flower subtended by two lateral branches	Common cyme
Multichasial / polychasial cyme	Flowers borne on more than two sides	—
Scapigerous cyme umbel	Leafless scape from ground bears umbellate cyme covered by spathes	Onion

▢ Special Inflorescence:

Table 1: Special Inflorescences

Type	Feature	Examples / Fruit
Cyathium	Cup-shaped involucre; looks like single flower; one female flower surrounded by many male flowers; ratio 1:many or 1:5	Euphorbia
Hypanthodium	Fleshy pear/flask-shaped receptacle with hollow cavity	Ficus; develops into syconus fruit
Verticillaster	Biparous/dichasial cyme ending in uniparous cyme; condensed cyme	Labiatae: Ocimum, Salvia, mint

📚

FLOWER

▢ Introduction:

Table 1: Flower Basics

Feature	Point
Flower	Modified shoot with condensed internodes and floral parts as modified leaves
Function	Forms fruit and seed; helps reproduction
Cauliflory / trunkiflory	Flowers develop on old stem from dormant bud
Largest flower	Rafflesia
Smallest flower	Wolffia microscopica
Non-essential parts	Sepals, petals
Essential parts	Stamen, carpel
Pedicel	Stalk of flower
Peduncle	Stalk of inflorescence
Petiole	Stalk of leaf
Thalamus / torus	Swollen end of pedicel; 4 nodes and short internodes

▢ Flower Characters:

Table 1: General Flower Types

Type	Meaning	Examples
Complete flower	All 4 whorls present: calyx, corolla, androecium, gynoecium	—
Incomplete flower	One or more whorls absent	—
Bisexual / monoclinous / perfect / intersexual	Both androecium and gynoecium present	Mustard, hibiscus, Datura, pea, onion, grass, disc floret
Unisexual / diclinous	Only one sex present	Cucumber, ray floret
Pistillate	Only gynoecium	Ray floret
Staminate	Only androecium	Cucurbits, papaya, mulberry
Monoecious	Male and female flowers on same plant	Maize, castor, Colocasia, Ficus, cucurbits, Pinus, mango
Dioecious	Male and female flowers on separate plants	Cycas, papaya, mulberry, lapsi
Polygamous	Unisexual, bisexual and neuter flowers on same plant	Mango, Polygonum

▢ Flower Opening and Arrangement:

Table 1: Flower Conditions

Condition	Meaning	Examples
Cleistogamous	Flowers never open; do not expose pollen	Arachis, Oxalis, Viola, Mirabilis, balsam
Chasmogamous	Flowers open at maturity	Commelina benghalensis has both cleistogamy and chasmogamy
Cyclic	Floral parts arranged in circles	—
Acyclic / spiral	Floral parts arranged spirally; primitive angiosperm character	—
Bracteate	Flower covered by bract/involucre	Compositae, Euphorbiaceae, Gramineae
Ebracteate	Bract absent	Brassicaceae, Solanaceae

▢ Symmetry and Ovary Position:

Table 1: Symmetry and Floral Position

Type	Meaning	Examples
Actinomorphic	Radially symmetrical; divisible into two equal halves by any vertical plane	Cruciferae, Mimosaceae, Malvaceae, Liliaceae, disc floret
Zygomorphic	Bilaterally symmetrical; only one plane divides into two equal halves	Papilionaceae, Caesalpiniaceae, Graminae, ray floret
Slightly zygomorphic	Due to oblique ovary	Solanaceae
Hypogynous	Ovary superior	Brassicaceae
Perigynous	Ovary half-inferior / middle	Pea, bean, rose
Epigynous	Ovary inferior	Compositae, cucurbits

▢ Floral Whorl Condition:

Table 1: Calyx and Corolla Condition

Type	Meaning	Examples
Achlamydous	Calyx and corolla absent	Euphorbiaceae, Piperaceae
Monochlamydous / Haplochlamydous	Only one whorl present, either calyx or corolla	Polygonaceae, Gramineae, Liliaceae
Dichlamydous	Both calyx and corolla present	Most flowers
Perianth	Calyx and corolla not differentiated	Tepals

▢ Floral Internodes:

Table 1: Internodes of Flower

Structure	Internode	Position	Examples
Anthophore	1st internode	Between calyx and corolla	Silene
Androphore / gonophore	2nd internode	Between corolla and androecium	Passiflora
Gynophore	3rd internode	Between androecium and gynoecium	Gynandropsis, Capparis
Gynandrophore / androgynophore	Both androphore and gynophore distinct	—	Gynandropsis, Cleome
Carpophore	Raised thalamus between fused carpels	—	Coriander

▢ Dichogamy and Anthesis:

Table 1: Maturation Terms

Term	Meaning	Examples
Dichogamy	Pollen grains and ovules mature at different times	—
Protandry	Pollen grains mature earlier	Salvia, cotton, sunflower, rose, moss
Protogyny	Ovules / carpels mature earlier	Ficus, Magnolia, four o'clock plant
Anthesis	Opening of floral bud / time when flower is fully open and functional	—

▢ Calyx:

Table 1: Calyx / Sepal

Feature	Point
Position	Outermost floral whorl
Unit	Sepal
Colour	Usually green / sepaloid
Petaloid sepal	Sepal with colour other than green
Function	Protection of bud
Polysepalous	Sepals free
Gamosepalous	Sepals fused
Modified sepals	Pappus or scales in Compositae
Epicalyx	Additional whorl of sepal-like bracteoles; Malvaceae, Cucurbitaceae

❖ Sepal Persistence:

Table 1: Sepal Duration

Type	Feature	Examples
Caducous	Falls immediately after flower opens	Papaver
Deciduous	Withers after fertilization during fruit maturation	Cucurbitaceae, Malvaceae, Brassicaceae
Persistent	Does not fall after fertilization	Solanaceae

▢ Corolla:

Table 1: Corolla / Petal

Feature	Point
Unit	Petal
Colour	Various
Function	Attract insects for pollination
Polypetalous	Petals free
Gamopetalous	Petals fused

❖ Corolla Shapes:

Table 1: Corolla Forms

Shape	Feature	Example
Cruciform	Cross-like	Cruciferae
Papilionaceous	Butterfly-like	Pea family / Papilionaceae
Ligulate	Strap / tongue-like	Ray floret of Compositae
Tubular	Tube-like	Disc floret of Compositae, Solanaceae
Campanulate	Inverted bell-shaped	Solanaceae
Bilabiate	Two-lipped zygomorphic gamopetalous corolla	Ocimum
Personate	Masked bilabiate with narrow opening	Antirrhinum
Infundibuliform	Funnel-shaped	Datura

❖ Aestivation:

Table 1: Aestivation Types

Type	Feature	Examples
Valvate	Margins meet but do not overlap	Cruciferae, Mimosaceae, Asteraceae
Contorted / twisted	Margins overlap regularly	Malvaceae petals
Quincuncial	Two outer, two inner, one twisted	—
Descending imbricate / vexillary	Posterior petal overlaps lateral; laterals overlap anterior	Papilionaceae
Ascending imbricate	Posterior overlapped by lateral; lateral overlapped by anterior	Caesalpiniaceae

▢ Perianth:

Table 1: Perianth

Term	Meaning
Perianth	Indistinct calyx and corolla
Tepal	Unit of perianth
Polyphyllous	Tepals free
Gamophyllous	Tepals fused
Epiphyllous	Stamen fused with tepal; Liliaceae
Lodicule	Structure equivalent to perianth in grasses

▢ Androecium:

❖ Introduction:

Table 1: Androecium

Feature	Point
Nature	Male reproductive whorl
Unit	Stamen
Anther	Male sporophyll / fertile part
Connective	Vascular supply to anther
Filament	Stalk
Typical anther	Dithecous / bithecous and tetrasporangiate
Each anther lobe	2 pollen sacs
Monothecous anther	Single lobe and bisporangiate; Malvaceae
Monosporangiate anther	Arceuthobium
Pollinium	Pollen grains in sac-like structure; Asclepiadaceae, Orchidaceae
Staminode	Sterile undeveloped stamen

❖ Stamen Position and Fusion:

Table 1: Stamen Conditions

Condition	Meaning	Example
Introse	Stamens remain inside closed flower	Pisum sativum
Extrose	Stamens longer than petals and protrude	Malvaceae
Polyandrous	Stamens free	—
Episepalous	Stamen fused with sepals	Verbena
Epipetalous	Stamen fused with petals	Malvaceae
Epiphyllous	Stamen fused with tepals	Liliaceae
Gynandrous	Stamen fused with carpel forming gynostegium	Calotropis

❖ Anther Fixation:

Table 1: Anther Fixation

Type	Feature	Example
Basifixed	Filament attached at base of anther	Brassicaceae, Solanaceae
Dorsifixed	Filament attached dorsally	Legumes
Adnate	Filament attached along whole length of anther	Magnoliaceae
Versatile	Anther attached near middle of connective and freely movable	Graminae

❖ Cohesion of Stamens:

Table 1: Cohesion of Stamens

Type	Fusion	Example
Synandrous	Both anther and filament fused	Cucurbitaceae
Syngenesious	Anthers fused, filaments free	Compositae / Asteraceae
Monoadelphous	Filaments fused into one bundle; anthers free	Malvaceae
Diadelphous	Filaments fused into two bundles; anthers free	Papilionaceae
Polyadelphous	Filaments fused into more than two bundles; anthers free	Citrus, castor, Bombax

❖ Length of Stamens:

Table 1: Stamen Length

Type	Feature	Example
Didynamous	4 stamens; outer 2 long, inner 2 short	Labiatae / Ocimum
Tetradynamous	6 stamens; outer 2 short, inner 4 long	Brassicaceae
Heterostemony	Stamens of different lengths	Caesalpiniaceae

▢ Gynoecium:

❖ Introduction:

Table 1: Gynoecium / Carpel

Term	Meaning
Gynoecium	Female reproductive whorl
Unit	Carpel
Carpel parts	Stigma, style, ovary
Pistil	Single carpel or fused group of carpels
Simple gynoecium	One carpel / monocarpellary
Compound gynoecium	Two or more carpels
Apocarpous	Carpels free
Syncarpous	Carpels fused

❖ Carpel vs Pistil:

Table 1: Carpel vs Pistil

Carpel	Pistil
Female unit consisting of stigma, style and ovary	May be one carpel or fused collection of carpels
Number counted by separate carpels	Number counted by separate ovaries
Can be free or fused	Represents functional female reproductive structure

❖ Style and Stigma:

Table 1: Style and Stigma

Feature	Type / Example
Terminal style	Arises from top of ovary; Brassicaceae, Solanaceae
Lateral style	Arises from lateral side of ovary; Graminae
Gynobasic style	Arises from base of ovary; Labiatae e.g. Salvia, Ocimum
Bifid stigma	Compositae, Solanaceae, Brassicaceae
Trifid stigma	Liliaceae
Tetrafid stigma	Labiatae
Pentafid stigma	Malvaceae

❖ Ovary Locules:

Table 1: Types of Ovary by Locule

Type	No. of chambers
Unilocular	1
Bilocular	2
Trilocular	3
Tetralocular	4
Pentalocular	5
Multilocular	Many

❖ Placentation:

◉ Definition: Arrangement of ovules in ovary

Table 1: Types of Placentation

Type	Mnemonic	Examples / Family
Parietal	PCC	Cruciferae, Cucurbitaceae
Axile	SoMaLiA	Solanaceae, Malvaceae, Liliaceae
Marginal	MaLe	Leguminosae / Papilionaceae
Basal	BAG	Asteraceae, Graminae

❖ Gynoecium by Carpel Number:

Table 1: Types of Gynoecium

Type	Number of carpels
Simple gynoecium / monocarpellary	1
Bicarpellary	2
Polycarpellary	Many

📚

HIGH-YIELD RECALL

Table 1: Morphology One-Liners

Fact	Answer
Study of form and structure	Morphology
Study of flowering plants / flowers	Anthology
First flowering plant appeared	Jurassic period
Leaf arrangement	Phyllotaxy
Young leaf arrangement in bud	Prefoliation
Individual young leaf arrangement	Ptyxis
Circinate ptyxis	Fern, Cycas, banana
Inflorescence flower arrangement	Anthotaxy
Flower stalk	Pedicel
Inflorescence stalk	Peduncle
Leaf stalk	Petiole
Swollen end of pedicel	Thalamus / torus
Root origin	Radicle
Lateral roots arise from	Pericycle
Root origin nature	Endogenous
Root lacks	Nodes, internodes, leaves, flowers
Nodulated roots	Legumes
Root nodule bacterium	Rhizobium
Pigment in root nodules	Leghaemoglobin
Breathing roots	Pneumatophores
Pneumatophore pores	Pneumatothodes
Mycorrhizal root lacks	Root cap and root hairs
Prop root	Ficus benghalensis
Stilt root	Sugarcane, maize
Velamen tissue	Epiphytic orchid root
Sweet potato root	Tuberous adventitious root
Stem origin	Plumule
Stem hairs	Usually multicellular
Stem branches arise	Exogenously
Culm	Grass family
Excurrent stem	Conifers
Pseudostem	Banana
Caudex	Cycas, coconut
Thorn	Modified stem / axillary bud
Spine	Modified leaf
Prickle	Superficial outgrowth
Lianas	Woody tropical climbers
Runner	Oxalis, Cynodon
Offset	Pistia, Eichhornia
Sucker	Banana, mint
Stolon	Strawberry
Bulb	Onion, garlic
Corm	Colocasia, Amorphophallus
Rhizome	Ginger, turmeric
Tuber	Potato
Phylloclade	Opuntia
Cladode	Asparagus
First leaf	Prophyll
All leaf types in plant	Phyllome
Single-leaf plant	Monophyllaea
Two-leaf plant	Welwitschia
Dicot leaf	Dorsiventral
Monocot leaf	Isobilateral
Petiole develops	Last
Bulbous petiole	Eichhornia
Phyllode	Australian acacia
Reticulate venation	Common in dicots
Parallel venation	Common in monocots
Racemose growth	Indeterminate
Cymose growth	Determinate
Most common inflorescence	Spike
Capitulum	Sunflower
Spadix	Colocasia, Arisaema
Cyathium	Euphorbia
Hypanthodium	Ficus
Verticillaster	Labiatae
Largest flower	Rafflesia
Smallest flower	Wolffia microscopica
Flower is	Modified shoot
Complete flower	Calyx + corolla + androecium + gynoecium
Bisexual flower	Androecium + gynoecium present
Cauliflory	Flower on old stem
Cleistogamy	Closed flower
Actinomorphic	Radially symmetrical
Zygomorphic	Bilaterally symmetrical
Hypogynous	Superior ovary
Epigynous	Inferior ovary
Calyx unit	Sepal
Corolla unit	Petal
Perianth unit	Tepal
Valvate aestivation	Margins meet, no overlap
Vexillary aestivation	Papilionaceae
Typical anther	Dithecous + tetrasporangiate
Monothecous anther	Malvaceae
Pollinium	Calotropis, orchids
Syngenesious stamens	Asteraceae
Monoadelphous stamens	Malvaceae
Diadelphous stamens	Papilionaceae
Tetradynamous stamens	Brassicaceae
Gynobasic style	Labiatae
Marginal placentation	Leguminosae
Axile placentation	Solanaceae, Malvaceae, Liliaceae
Parietal placentation	Cruciferae, Cucurbitaceae
Basal placentation	Asteraceae, Graminae

Q1.

Phylloclade and cladode are morphological adaptations for photosynthesis and water storage, found in

📅CEE MBBS 2025

Q2.

In which inflorescence does the main axis show definite growth and terminate in a flower?

📅CEE MBBS 2025

Q3.

A fruit formed from many free carpels of a single flower is:

📅CEE BDS 2024

Q4.

A phylloclade is a modified:

📅CEE BDS 2024

Q5.

Bicollateral vascular bundles commonly occur in:

📅CEE BDS 2024

Q6.

Stilt roots of sugarcane originate from the:

📅CEE MBBS 2023

Q7.

Phylloclades and cladodes are common adaptations of:

📅CEE BDS 2023

Q8.

A leaf lamina is typically attached to the stem through the:

📅CEE BDS 2023

Q9.

Which of the following is a fleshy berry in which the fruit wall (pericarp) forms much of the edible portion?

📅CEE BDS 2023

Q10.

The edible white flesh of coconut is:

📅CEE MBBS 2022

Q11.

The arrangement of petals in pea flowers is:

📅CEE MBBS 2022

Q12.

The inflorescence of sunflower is:

📅CEE MBBS 2021

Q13.

Which is an underground stem modification for storage and perennation?

📅CEE BDS 2021

Q14.

The edible fleshy part of litchi is the:

📅CEE BDS 2021

Q15.

An apocarpous gynoecium has:

📅CEE BDS 2021

Table 1: Morphology Basics

Table 1: Root, Stem, Leaf, Inflorescence and Flower

Table 1: Types of Phyllotaxy

Table 1: Prefoliation

Table 1: Root Characters

Table 1: Plantless Roots and Rootless Plants

Table 1: Storage Tap Roots

Table 1: Tap Root Modifications

Table 1: Storage Adventitious Roots

Table 1: Adventitious Root Modifications

Table 1: Stem Characters

Table 1: Aerial Erect Stem Types

Table 1: Twiners vs Climbers

Table 1: Types of Climbers

Table 1: Thorn vs Spine vs Prickle

Table 1: Sub-aerial Stem Modifications

Table 1: Trailers

Table 1: Underground Stem Modifications

Table 1: Bulb Types

Table 1: Special Stem Modifications

Table 1: Leaf Characters

Table 1: Leaf Surfaces

Table 1: Leaf Types by Insertion

Table 1: Leaf Types by Life Span

Table 1: Leaf Types by Origin and Function

Table 1: Leaf Parts

Table 1: Petiole Modifications

Table 1: Types of Venation

Table 1: Simple and Compound Leaves

Table 1: Solitary Flowers

Table 1: Racemose vs Cymose Inflorescence

Table 1: Simple Racemose Inflorescences

Table 1: Compound Racemose Inflorescences

Table 1: Cymose Types

Table 1: Special Inflorescences

Table 1: Flower Basics

Table 1: General Flower Types

Table 1: Flower Conditions

Table 1: Symmetry and Floral Position

Table 1: Calyx and Corolla Condition

Table 1: Internodes of Flower

Table 1: Maturation Terms

Table 1: Calyx / Sepal

Table 1: Sepal Duration

Table 1: Corolla / Petal

Table 1: Corolla Forms

Table 1: Aestivation Types

Table 1: Perianth

Table 1: Androecium

Table 1: Stamen Conditions

Table 1: Anther Fixation

Table 1: Cohesion of Stamens

Table 1: Stamen Length

Table 1: Gynoecium / Carpel

Table 1: Carpel vs Pistil

Table 1: Style and Stigma

Table 1: Types of Ovary by Locule

Table 1: Types of Placentation

Table 1: Types of Gynoecium

Table 1: Morphology One-Liners

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