Reproduction | CEE Academy

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ANGIOSPERM REPRODUCTION / FLOWER

▢ Typical Flower:

❖ Definition: Reproductive shoot of angiosperm

❖ Homology with Gymnosperms:

Table 1: Gymnosperm vs Angiosperm Homology

Angiosperm structure	Gymnosperm equivalent
Flower	Cone / Strobilus
Stamen	Microsporophyll
Anther / Pollen sac	Microsporangium
Pollen grain	Microspore
Germinating pollen / pollen with pollen tube	Male gametophyte
Carpel / Ovary	Megasporophyll
Ovule	Megasporangium
Embryo sac	Female gametophyte
Megaspore	Macrospore
Egg / Oosphere	Female gamete
Egg apparatus	Archegonium

▢ Male Reproductive Part:

❖ Androecium: Composed of stamens / microsporophylls

❖ Stamen:

Table 1: Parts of Stamen

Part	Nature / Function
Anther	Fertile part
Connective	Sterile part
Filament	Stalk

❖ Anther:

Table 1: Anther Structure

Feature	Point
Anther lobe	Present on either side of connective
Pollen sacs per lobe	2
Microsporangia per anther	4
Typical anther	Dithecous + tetrasporangiate
Dithecous anther	2 anther lobes + 4 microsporangia
Rare monosporangiate anther	Arceuthobium
Development in higher plants	Eusporangiate
Fern sporangium	Leptosporangiate e.g. Dryopteris

▢ Microsporogenesis:

❖ Definition: Development of microspores / pollen grains from microspore mother cell inside microsporangium / pollen sac

❖ Sequence:

Young anther → homogeneous meristematic cells + epidermis
Hypodermal archesporial cell differentiates
Archesporial cell divides periclinally
Outer primary parietal cell formed
Inner primary sporogenous cell formed
Primary parietal cell → anther wall layers
Primary sporogenous cell → microspore mother cells / MMC
MMC undergoes meiosis
Haploid pollen tetrad formed
Callose dissolves
Individual pollen grains released

❖ Anther Wall:

Table 1: Anther Wall Layers

Layer	Position	Features / Function
Epidermis	Outermost	Single-layered; thick; protective
Endothecium	Below epidermis	Radially elongated cells; fibrous thickening; hygroscopic; helps anther dehiscence
Middle layers	Between endothecium and tapetum	2–3 layers; ephemeral; degenerate at maturity
Tapetum	Innermost	Nutritive; large nuclei; dense cytoplasm; maximum at pollen tetrad stage

◉ Stomium: Thin-walled region of anther where dehiscence occurs

◉ Exothecium: Fibrous thickening in epidermis of Arceuthobium; gymnosperm-like feature

❖ Tapetum:

◉ Nature:

•
Innermost anther wall layer
•
Nutritive to pollen grains + developing pollen mother cells
•
Cells large, multinucleated, polyploid
•
Polyploidy due to endomitosis / endopolyploidy
•
Secretes enzymes + hormonal substances e.g. IAA

◉ Types:

Table 1: Types of Tapetum

Type	Other name
Amoeboid tapetum	Invasive / periplasmodial
Secretory tapetum	Glandular / parietal

◉ Products:

Table 1: Tapetal Products

Product	Nature / Function
Callase enzyme	Dissolves callose around pollen tetrad
Ubisch bodies / sphaeroids	Lipid bodies coated with sporopollenin; increase exine thickness
Sporopollenin	Hardest / most resistant plant substance; preserves pollen in fossils
Pollen kitt	Sticky; lipids + carotenoids; common in entomophilous pollen
Proteins	Help pollen compatibility recognition
IAA	Hormonal substance secreted by tapetum

◉ Ubisch Bodies: Produced by glandular tapetum

◉ Sporopollenin:

•
Hydrophobic
•
Not degraded by enzymes
•
Most resistant biological substance
•
Major cause of long-term pollen fossil preservation

❖ Special Points:

•
Tapetum = polyploid
•
Pollen tetrad = haploid
•
Most other anther tissues = diploid
•
Middle layer absent in Lemna and Wolffia
•
In Cyperaceae, 1 MMC forms 1 microspore
•
Pollen tetrad may be tetrahedral or isobilateral
•
Tetrahedral tetrad common in dicots
•
Isobilateral tetrad common in monocots
•
Polyspory = more than 4 pollens from 1 MMC; example Cuscuta
•
In Asclepiadaceae and Orchidaceae, pollen grains remain united as pollinium
•
Pollinium example → Calotropis, orchids

▢ Microgametogenesis:

❖ Definition: Formation of male gametophyte from functional pollen grain

❖ Study Terms:

Table 1: Pollen Study Terms

Term	Meaning
Palynology	Study of pollen morphology
Melittopalynology	Study of honey pollens
Iatropalynology	Study of pollen in criminal and medical aspects

❖ Pollen Grain:

Table 1: Pollen Grain

Feature	Point
Generation	First cell of gametophytic generation
Ploidy	Haploid
Shape	Globulose
Nucleus	Initially uninucleate
Appearance	Dust-like, yellowish, minute
Best definition	Partially developed male gametophyte
Fully developed male gametophyte	Germinating pollen grain with pollen tube

❖ Pollen Wall:

Table 1: Pollen Wall

Layer	Composition	Origin / Function
Exine	Sporopollenin + cutin	Thick, hard, resistant; derived from tapetum
Intine	Cellulose + pectin	Thin, elastic; forms pollen tube
Germ pore	Region with thin/absent exine	Pollen tube emerges

◉ Exine Layers:

•
Ectexine → tectum, columellae, foot layer
•
Endexine

◉ Intine Layers:

•
Ectintine
•
Endintine

◉ Germ Pore:

•
Dicots → usually 3 germ pores
•
Monocots → single germinal furrow

❖ Pollen Cells:

Table 1: Cells of Pollen Grain

Cell	Size	Nucleus	Function
Vegetative / Tube cell	Larger	Large; physiologically active	Forms pollen tube
Generative cell	Smaller	Small; genetically active	Forms 2 male gametes

❖ Pollination Stage:

Table 1: Pollen Stage at Pollination

Plant group	Stage
Most angiosperms	2-celled stage
Monocots e.g. sugarcane, maize	3-celled stage
Dicots e.g. Malvaceae, Cucurbitaceae	3-celled stage
Cycas	3-celled stage → 1 prothallial + 1 tube + 1 generative
Pinus	4-celled stage → 2 prothallial + 1 tube + 1 generative

◉ Angiosperm Male Gametophyte:

•
No prothallial cell
•
Mature male gametophyte = 3-celled + 3-nucleated
•
Formed by 3 divisions → 1 meiosis + 2 mitosis
•
2-celled mature pollen = formed by 1 meiosis + 1 mitosis

❖ Pollen Tube:

Table 1: Pollen Tube

Feature	Point
Origin	Intine
Composition	Pectin, callose, cellulose
Discovery	Amici
Term pollen	Nemec
Monosiphonous	Single pollen tube from 1 pollen grain
Polysiphonous	Many pollen tubes from 1 pollen grain; 6–14 in Cucurbitaceae, Malvaceae

◉ Growth Factor: Boron helps pollen grain / pollen tube growth

❖ Important Pollens:

Table 1: Special Pollen Points

Point	Example
Hay fever causing pollen	Ambrosia
Poisonous pollen	Serjania
Largest pollen	Cucurbits
Smallest pollen	Myosotis / forget-me-not
Androgenic haploid	Haploid produced from microspore / pollen grain

▢ Female Reproductive Part:

❖ Gynoecium: Composed of carpel / pistil / megasporophyll

❖ Carpel:

Table 1: Carpel

Part	Feature
Stigma	Receives pollen; present only in angiosperms
Style	Connects stigma and ovary
Ovary	Contains ovules

❖ Ovule:

◉ Definition: Integumented indehiscent megasporangium which becomes seed after fertilization

◉ Other Name: Seed bud

◉ Arrangement: Placentation = arrangement of ovules inside ovary

◉ Parts:

Table 1: Parts of Ovule

Part	Meaning / Point
Micropyle	Opening of ovule; formed by inner integument
Nucellus	Main parenchymatous body of ovule; first formed cell of ovule
Integument	Surrounds ovule except micropyle
Chalaza	Junction of integuments and nucellus; basal part; opposite micropyle; most active part
Funicle	Stalk attaching ovule to placenta
Hilum	Point of attachment of ovule body to funicle
Raphe	Bulged part formed by funicle on ovule body
Endostome	Space between nucellus and inner integument near micropyle

❖ Placentation:

Table 1: Types of Placentation

Type	Examples / Family
Marginal	Leguminaceae
Parietal	Cruciferae, Cucurbitaceae
Axile	Solanaceae, Malvaceae, Liliaceae
Basal	Compositae, Poaceae
Superficial	Nymphaea, Nelumbo
Free central	Dianthus, Salvia

◉ Mnemonics:

•
Marginal → Ma Le → Leguminaceae
•
Axile → So Ma Li A → Solanaceae, Malvaceae, Liliaceae

▢ Forms of Ovule:

❖ Based on Orientation:

Table 1: Types of Ovule by Orientation

Type	Feature	Examples
Orthotropous / Atropous / Erect	Straight; micropyle, funicle, chalaza in one line; primitive + simplest	Gymnosperms except Pinus, Cycas, Piperaceae, Polygonaceae
Anatropous / Inverted	Ovule inverted 180°; micropyle close to funicle; most common	Angiosperms, Pinus
Hemianatropous / Hemitropous	Ovule at right angle to funicle	Ranunculus
Campylotropous	Ovule body curved but embryo sac straight	Capsella, Capparis, Leguminosae, Cruciferae
Amphitropous	Curved ovule with horse-shoe shaped embryo sac	Papaveraceae, Alismaceae
Circinotropous	Ovule coiled by funicle; micropyle upward	Cactaceae e.g. Opuntia

◉ Special:

•
Cycas → orthotropous + unitegmic
•
Pinus → anatropous + unitegmic
•
Mnemonic → P An = Pinus Anatropous

❖ Based on Integuments:

Table 1: Types of Ovule by Integument Number

Type	Meaning	Examples
Ategmic	No integument	Santalum, Loranthus
Unitegmic	Single integument	Gymnosperms, Cycas, Pinus, higher dicots, Compositae
Bitegmic	Two integuments	Common in angiosperms, monocots
Tritegmic	Three integuments	Asphodelus

◉ Integument Derivatives:

•
Testa → outer integument
•
Tegmen → inner integument
•
Caruncle in Ricinus → outer integument
•
Asphodelus covering / aril-like structure → integument-derived
•
All ovular cells outside embryo sac are diploid → integument, nucellus, funicle, hilum

❖ Specific Ovular Structures:

Table 1: Ovule-associated Structures

Structure	Origin / Meaning	Example / Function
Endothelium	Specialized nutritive tissue from innermost integument	Integumentary tapetum; Asteraceae
Obturator	Ovular structure guiding pollen tube to micropyle	From funicle / placenta
Caruncle	Outgrowth from outer integument	Ricinus; absorbs water
Perisperm	Remnant of nucellus	Zingiber
Aril	Develops from funicle	Edible part of Litchi chinensis
Aril in litchi	Third integument-like covering	Edible part

▢ Megasporogenesis:

❖ Definition: Development of megaspores inside megasporangium / ovule

❖ Sequence:

Hypodermal nucellar cell becomes archesporial cell
Archesporial cell divides periclinally
Outer primary parietal cell formed
Inner primary sporogenous cell formed
Primary parietal cell divides anticlinally → wall of embryo sac
Primary sporogenous cell enlarges → megaspore mother cell / MMC
MMC undergoes meiosis
4 megaspores formed in linear tetrad
3 micropylar megaspores degenerate
1 chalazal megaspore remains functional

❖ Special Cases:

•
Balanophora → micropylar megaspore functional
•
Casuarina → any one of 4 megaspores functional

▢ Megagametogenesis:

❖ Definition: Formation of female gametophyte / embryo sac from functional megaspore

❖ Sequence:

Functional megaspore undergoes 3 mitotic divisions
8 nuclei formed
4 nuclei at micropylar end + 4 nuclei at chalazal end
One nucleus from each pole migrates to centre
Two polar nuclei fuse during fertilization
Secondary nucleus / definitive nucleus formed
3 chalazal cells → antipodal cells
3 micropylar cells → egg apparatus
Mature embryo sac becomes 7-celled and 8-nucleated

❖ Embryo Sac Structure:

Table 1: Mature Angiospermic Embryo Sac

Region	Cells / Nuclei	Function
Micropylar end	Egg apparatus → 1 egg + 2 synergids	Fertilization + pollen tube guidance
Central region	2 polar nuclei / secondary nucleus	Forms endosperm after triple fusion
Chalazal end	3 antipodal cells	Degenerate later

❖ Synergids:

•
Contain filiform apparatus
•
Absorb nutrients
•
Guide pollen tube by chemical secretion
•
2 synergids direct pollen tube

❖ Polygonum Type:

Table 1: Polygonum Type Embryo Sac

Feature	Point
Type	Monosporic
Cells	7-celled
Nuclei	8-nucleated
Nature	Most simple, primitive, normal type
First discovered in	Polygonum divaricatum
Discovered by	Strasburger
Formation	1 meiosis + 3 mitosis

❖ Embryo Sac Types:

Table 1: Types of Embryo Sac

Type	Development	Examples
Monosporic	From 1 megaspore	Polygonum, Oenothera
Bisporic / Allium type	From 2 megaspore nuclei	Onion
Tetrasporic	From 4 megaspore nuclei	Adoxa

❖ Special Points:

•
Female gametophyte = embryo sac / megagametophyte
•
All embryo sac cells haploid except secondary nucleus / polar nuclei
•
Secondary nucleus = only diploid nucleus of embryo sac
•
Largest cell of embryo sac = central / secondary cell
•
Constant feature of embryo sac = egg cell / oosphere
•
Pollen tube finally discharges gametes into synergid
•
Growth of pollen tube toward embryo sac = chemotropic
•
Nuclei at centre = polar nuclei
•
Meiosis for n pollen grains = n/4
•
Meiosis for n functional megaspores = n

▢ Pollination:

❖ Definition: Transfer of pollen grains from anther to stigma

❖ Types:

Table 1: Self vs Cross Pollination

Feature	Self-pollination / Autogamy	Cross-pollination / Allogamy
Meaning	Pollen transferred to stigma of same flower / same plant	Pollen transferred to stigma of different plant
Purity	Maintains purity of race	Produces variation
Pollen wastage	Less	More
Offspring	Less variable	Healthier / more adaptable
New varieties	Less chance	May be produced

❖ Cross Pollination Types:

Table 1: Types of Allogamy

Type	Meaning
Geitonogamy	Between flowers of same plant
Xenogamy	Between flowers of different plants of same species
Hybridization	Between flowers of different species

❖ Contrivances for Self Pollination:

•
Bisexuality / Monocliny
•
Cleistogamy → closed flowers
•
Homogamy → male and female parts mature at same time

❖ Cleistogamy Examples:

•
Arachis hypogaea / groundnut
•
Pisum sativum / pea
•
Oxalis
•
Commelina benghalensis → both cleistogamy + chasmogamy
•
Cleistogamy is accompanied by geocarpy

❖ Contrivances for Cross Pollination:

Table 1: Outbreeding Devices

Device	Meaning / Example
Dicliny / Unisexuality	Monoecious or dioecious flowers
Monoecious	Male + female flowers on same plant e.g. maize, cucurbit, castor
Dioecious	Male + female flowers on different plants e.g. papaya, Cannabis sativa, Vallisneria
Chasmogamy	Open flowers
Dichogamy	Male and female parts mature at different times
Protandry	Male part matures first
Protogyny	Female part matures first
Heterostyly	Stamens, style and stigma at different heights
Herkogamy	Natural barrier between anther and stigma
Self sterility / self incompatibility	Pollen fails to germinate on stigma of same flower
Pollen pre-potency	Pollen from another flower germinates faster than own pollen

◉ Herkogamy Example:

•
Best herkogamy → Calotropis
•
Barrier → gynostegium disc
•
Pollen grains occur in sacs called pollinia
•
Union of stigma with pollinia = gynostegium

❖ Agents of Pollination:

Table 1: Pollination Agents

Agent	Meaning	Examples	Adaptations
Anemophily	By wind	Gymnosperms, Cycas, Pinus, grasses, rice, wheat, maize	Small inconspicuous flowers; abundant pollen; small, light, smooth, dry, unwettable pollen; versatile anther; large hairy/feathery stigma
Hydrophily	By water	Vallisneria, Ceratophyllum, Zostera, Najas	Large sticky stigma
Entomophily	By insects	Bees, ants	Large coloured scented flowers; nectar; sticky rough large pollen
Malacophily	By snails/slugs	Colocasia, Lemna	Animal pollination
Ophiophily / Serpentophily	By snakes	Arisaema, Rauvolfia serpentina	Snake-associated flowers
Ornithophily	By birds	Sunbirds, hummingbirds, Bombax, bottle brush / Callistemon, Simal	Bird-attracting flowers
Chiropterophily	By bats	Anthocephalus, Adansonia, Kigelia, sausage tree, Bauhinia	Bat-attracting flowers
Other agents	Animals	Squirrels in Gulmohar, elephants in Rafflesia	Specialized animal interaction

◉ Hydrophily Types:

•
Epihydrophily → pollination on water surface e.g. Vallisneria
•
Hypohydrophily → pollination under water e.g. Ceratophyllum, Zostera, Najas

◉ Mechanisms:

Table 1: Special Pollination Mechanisms

Mechanism	Example
Turn-pipe / lever mechanism	Salvia
Translator mechanism	Calotropis
Door-trap mechanism	Ficus → gall wasp
Fly-trap mechanism	Aristolochia
Obligate symbiosis	Yucca + Pronuba moth
Censor mechanism	Poppy

▢ Fertilization:

❖ Definition: Fusion of male and female gametes to form zygote

❖ Siphonogamy: Male gametes carried to embryo sac by pollen tube

❖ Pollen Tube Entry into Ovule:

Table 1: Types of Pollen Tube Entry

Type	Entry route	Example
Porogamy	Through micropyle	Most common
Chalazogamy / Basigamy	Through chalaza	Casuarina
Mesogamy	Through integument	Cucurbita

❖ Important Points:

•
Most active part of ovule = chalaza
•
Pollen tube invariably enters embryo sac at micropylar end
•
Pollen tube secretes pectinases and hydrolytic enzymes to create path in style
•
Movement of pollen tube = chemotactic
•
Pollen tube attracted by synergids through filiform apparatus
•
Pollen tube releases 2 male gametes + degenerating tube nucleus into synergid

❖ Double Fertilization:

Table 1: Double Fertilization

Feature	Point
Unique to	Angiosperms
Discovered by	Nawaschin
Discovered in	Fritillaria and Lilium
Nuclei involved	5 nuclei
Gametes involved	3 gametes
Syngamy	Male gamete + egg → zygote
Triple fusion	Male gamete + 2 polar nuclei / secondary nucleus → primary endosperm nucleus

▢ Endosperm:

❖ Definition: Storage tissue supplying nutrition to developing embryo

❖ Origin: Primary endosperm nucleus / PEN formed by triple fusion

❖ Features:

•
Cells generally isodiametric
•
Thin-walled
•
Usually without pits
•
Angiosperm endosperm = post-fertilization tissue
•
Gymnosperm endosperm = pre-fertilization female gametophyte

❖ Gymnosperm vs Angiosperm Endosperm:

Table 1: Endosperm Difference

Feature	Gymnosperm	Angiosperm
Time of formation	Before fertilization	After fertilization
Nature	Female gametophyte	Product of triple fusion
Ploidy	Haploid	Usually triploid

❖ Types by Development:

Table 1: Types of Endosperm

Type	Feature	Examples / Notes
Nuclear type	Nuclear divisions without immediate wall formation	Most common; Malvaceae, Papilionaceae
Cellular type	Wall formation after each nuclear division	Magnoliaceae
Helobial type	Intermediate between nuclear and cellular	Mostly monocots
Coconut endosperm	Both nuclear + cellular	Coconut milk = liquid endosperm

❖ Special Points:

•
Aleurone layer = proteinaceous peripheral layer of cereal endosperm
•
Aleurone layer present in maize/cereals
•
No endosperm in Orchidaceae, Podostemaceae, Trapaceae → TOP
•
Coconut milk contains auxins, cytokinins, GA and induces cytokinesis
•
Milky maize endosperm induces cytokinesis
•
Zeatin extracted from milky endosperm of maize
•
Mature endosperm lacks stimulatory property

❖ Seed Types by Endosperm:

Table 1: Endospermic vs Non-endospermic Seeds

Type	Meaning	Examples
Non-endospermic / Exalbuminous	Endosperm absent at maturity	Gram, pea, bean, tamarind, orchids
Endospermic / Albuminous	Endosperm persists at maturity	Wheat, rice, barley, poppy, palms, maize

❖ Xenia & Metaxenia:

Table 1: Xenia vs Metaxenia

Term	Meaning	Example
Xenia	Direct effect of pollen on endosperm character	Maize
Metaxenia	Direct effect of pollen on structures outside embryo sac/endosperm e.g. seed coat or fruit wall	Date palm

▢ Embryogenesis:

❖ Definition: Development of embryo from zygote by division and differentiation

❖ Zygote: Fertilized egg / 2n

❖ Embryo: Future tiny plant inside seed

❖ Tigellum: Main axis of embryo

❖ Hofmeister: Proposed embryo originates from existing cell of embryo sac, not from pollen tube

❖ Dicot vs Monocot Embryo:

Table 1: Embryo Development

Feature	Dicot embryo	Monocot embryo
Cotyledons	Two	One
Common type	Onagrad / Ranunculaceous type	Grass embryo special
Embryonal axis	Present with 2 lateral cotyledons	Terminal cells form embryo
Epicotyl	Above cotyledon attachment	Present
Hypocotyl	Below cotyledon attachment	Below scutellum attachment
Plumule	Embryonic shoot at end of epicotyl	Protected by coleoptile in grasses
Radicle	Embryonic root at end of hypocotyl	Protected by coleorhiza in grasses
Grass cotyledon	—	Scutellum

❖ Nutrition of Embryo:

Table 1: Nutritive Tissues

Tissue	Meaning / Example
Endosperm	Main nutritive tissue
Perisperm	Remnant / persistent nucellus around embryo
Chalazosperm	Nucellar cells in chalazal region storing fats and starch; substitute for endosperm; found in Cyanastrum

❖ Polyembryony:

◉ Definition: Development of more than one embryo in same seed

◉ Discovered By: Leeuwenhoek in citrus

◉ Occurrence: Very common in gymnosperms

Table 1: Types of Polyembryony

Type	Cause	Example
Simple polyembryony	More than one embryo sac	Brassica
Mixed polyembryony	More than one pollen tube enters embryo sac; extra male gametes fuse with synergids/antipodals	Allium
Cleavage polyembryony	Embryo cleaves into two or more embryos	Orchids
Adventive polyembryony	Diploid nucellar / integument cells develop into embryos	Citrus

▢ Seed:

❖ Definition: Mature / ripened ovule

❖ Parts:

•
Seed coat
•
Embryo
•
Endosperm

❖ Seed Coat:

Table 1: Seed Coat Derivatives

Structure	Origin
Seed coat	Integuments of ovule
Testa	Outer integument
Tegmen	Inner integument
Aril	Third integument-like covering / funicle-derived in some seeds e.g. litchi
Caruncle	Spongy outgrowth near micropyle from outer integument; absorbs water

❖ Seed Size:

Table 1: Seed Extremes

Point	Example
Smallest / minutest seeds	Orchids
Lightest seeds	Orchid dust seeds
Largest seed	Double coconut / Lodoicea maldivica
Largest seed nature	Bilobed

❖ Exalbuminous vs Albuminous Seeds:

Table 1: Seed Types

Feature	Exalbuminous / Non-endospermic	Albuminous / Endospermic
Food stored in	Cotyledons	Endosperm
Common in	Dicots	Monocots
Endosperm at maturity	Absent / used up	Present
Examples	Bean, gram, pea	Wheat, rice, maize

❖ Monocot Seed Special:

•
Embryo small
•
Single cotyledon = scutellum
•
Embryonal axis covered by coleoptile
•
Radicle protected by coleorhiza

❖ First Emergence: Radicle is first part to emerge from seed

❖ Germination:

Table 1: Epigeal vs Hypogeal Germination

Type	Feature	Example
Epigeal	Cotyledons pushed above soil	Bean
Hypogeal	Cotyledons remain inside soil	Pea

▢ Amphimixis & Apomixis:

❖ Amphimixis: Normal sexual reproduction with meiosis + fertilization

❖ Apomixis:

◉ Definition: Abnormal reproduction without meiosis and syngamy / fertilization

◉ Term Given By: Winkler

◉ Types:

Table 1: Types of Apomixis

Type	Meaning	Examples
Vegetative reproduction	Plant develops from part other than seed	Bulbils, suckers, runners, stolons
Agamospermy	Seed formed but embryo develops without meiosis + fertilization	Seminiferous apomixis
Adventive embryony	Embryo from sporophytic tissues like nucellus/integument	Citrus, mango
Diplospory / generative apospory	MMC develops into diploid embryo sac without reduction division	Diploid embryo sac
Apospory / somatic apospory	Embryo sac develops directly from nucellus cell without meiosis	Ranunculus, Rubus, Parthenium

❖ Related Terms:

Table 1: Related Reproductive Terms

Term	Meaning	Point / Example
Apogamy	Embryo from synergids/antipodals without fertilization	Cells other than egg inside embryo sac
Parthenogenesis	Embryo from unfertilized egg	Helps form azygospore
Parthenocarpy	Fruit development without pollination and fertilization	Term by Noll; fruits seedless

◉ Parthenocarpic Fruits:

•
Banana
•
Papaya
•
Guava
•
Pineapple
•
Apple
•
Grapes
•
Cucurbita

◉ Artificial Parthenocarpy: Induced by powdered pollens and pollen extracts

▢ Fruit:

❖ Definition: Mature / ripened ovary

❖ Main Types:

Table 1: Main Fruit Types

Type	Origin	Example / Note
Simple fruit	Monocarpellary or syncarpous ovary of single flower	Dry or fleshy
Aggregate fruit / Etaerio	Apocarpous pistil of single flower	Collection of simple fruits
Multiple / Composite fruit	Inflorescence	Sorosis, syconus

❖ Dry Fruits:

◉ Dehiscent / Capsular:

Table 1: Dehiscent Fruits

Fruit	Feature	Examples
Siliqua	Elongated, linear, many-seeded; superior bicarpellary unilocular ovary; parietal placentation; dehisces from base to apex	Cruciferae
Silicula	Short, flat siliqua	Iberis, Capsella
Capsule	From multicarpellary syncarpous ovary	Cotton, lady's finger, poppy, Datura
Legume / Pod	From superior monocarpellary gynoecium; dehisces by both sutures	Pea, gram, bean
Follicle	From superior gynoecium; dehisces by one suture	Calotropis

◈ Capsule Dehiscence:

Table 1: Capsule Dehiscence Types

Type	Example
Poricidal	Opium poppy / Papaver somniferum, Argemone
Loculicidal	Cotton, lady's finger
Septicidal	Linum
Septifragal	Datura

◉ Indehiscent / Achenial:

Table 1: Indehiscent Dry Fruits

Fruit	Feature	Examples
Cypsela	From inferior bicarpellary ovary	Compositae
Caryopsis	From monocarpellary superior ovary; pericarp + testa fused	Graminae / Poaceae
Achene	Monocarpellary superior unilocular ovary; pericarp free from seed coat except one point	Mirabilis
Nut	One-seeded; superior syncarpous pistil; hard woody/leathery pericarp	Litchi, oak, cashew nut, water chestnut
Samara	One/two-seeded winged fruit; wings from pericarp	Winged fruits

◉ Schizocarpic:

•
Lomentum → groundnut
•
Cremocarp
•
Regma → castor
•
Carcerulus
•
Double samara

❖ Fleshy Fruits:

Table 1: Fleshy / Succulent Fruits

Fruit	Example
Berry / Bacca	Tomato
Drupe	Mango
Pepo	Cucumber
Pome	Apple
Hesperidium	Orange, lemon
Amphisarca	Bael
Balausta	Pomegranate

❖ Aggregate Fruits:

Table 1: Etaerio Fruits

Type	Example / Note
Etaerio of drupes	Aggregate of small drupes
Etaerio of achenes	Aggregate of achenes
Etaerio of follicles	Aggregate of follicles

❖ Multiple Fruits:

Table 1: Composite Fruits

Type	Inflorescence	Examples
Sorosis	Catkin / spike-like inflorescence	Jackfruit, mulberry, pineapple
Syconus	Hypanthodium inflorescence	Ficus

❖ Family-wise Fruit:

Table 1: Fruit Types of Important Families

Family	Fruit
Brassicaceae / Cruciferae	Siliqua / Silicula
Solanaceae	Capsule / Berry
Leguminosae	Legume / Pod
Asteraceae	Cypsela
Graminae / Poaceae	Caryopsis

▢ High-Yield Recall:

Table 1: Angiosperm Reproduction One-Liners

Fact	Answer
Stamen equivalent	Microsporophyll
Carpel equivalent	Megasporophyll
Anther equivalent	Microsporangium
Ovule equivalent	Megasporangium
Embryo sac	Female gametophyte
Dithecous anther	Tetrasporangiate
Monosporangiate anther	Arceuthobium
Anther dehiscence region	Stomium
Anther dehiscence layer	Endothecium
Nutritive layer of anther	Tapetum
Callase enzyme	Dissolves callose
Hardest plant substance	Sporopollenin
Study of pollen	Palynology
Pollen tube discovered by	Amici
Term pollen given by	Nemec
Pollen tube formed from	Intine
Pollen tube growth helped by	Boron
Hay fever pollen	Ambrosia
Poisonous pollen	Serjania
Largest pollen	Cucurbits
Smallest pollen	Myosotis
Stigma present only in	Angiosperms
Most active part of ovule	Chalaza
Most common ovule	Anatropous
Primitive ovule	Orthotropous
Cycas ovule	Orthotropous + unitegmic
Pinus ovule	Anatropous + unitegmic
Embryo sac type	Polygonum type
Polygonum embryo sac	Monosporic, 7-celled, 8-nucleated
Polygonum type discovered by	Strasburger
Only diploid nucleus in embryo sac	Secondary nucleus
Pollen tube guidance	Synergids / filiform apparatus
Self pollination	Autogamy
Cross pollination	Allogamy
Wind pollination	Anemophily
Water pollination	Hydrophily
Insect pollination	Entomophily
Bird pollination	Ornithophily
Bat pollination	Chiropterophily
Lever mechanism	Salvia
Translator mechanism	Calotropis
Gall wasp pollination	Ficus
Yucca pollinator	Pronuba moth
Most common pollen tube entry	Porogamy
Chalazogamy example	Casuarina
Mesogamy example	Cucurbita
Double fertilization discovered by	Nawaschin
Double fertilization discovered in	Fritillaria, Lilium
Double fertilization unique to	Angiosperms
Endosperm in angiosperm	Triploid + post-fertilization
Endosperm in gymnosperm	Haploid + pre-fertilization
Most common endosperm	Nuclear type
Cytokinin from maize	Zeatin
No endosperm families	Orchidaceae, Podostemaceae, Trapaceae
Polyembryony discovered by	Leeuwenhoek
Polyembryony common in	Gymnosperms
Seed	Mature ovule
Fruit	Mature ovary
Testa	Outer integument
Tegmen	Inner integument
Smallest seeds	Orchids
Largest seed	Double coconut
Apomixis term	Winkler
Parthenocarpy term	Noll
First part during germination	Radicle
Siliqua family	Cruciferae / Brassicaceae
Legume fruit	Leguminosae
Cypsela fruit	Asteraceae
Caryopsis fruit	Poaceae / Graminae

Q1.

Embryo sac is found in: [IE 2008]

📅IE 2008

Q2.

Zeatin is obtained by: [IOM 1997]

📅IOM 1997

Q3.

Mechanical dispersion of seed takes place in: [IOM 1999]

📅IOM 1999

Q4.

In a seed, food is generally stored in: [BPKIHS 2005]

📅BPKIHS 2005

Q5.

If pollen of a flower, reaches on a genetically different plant, then it is: [IOM 2005)

📅IOM 2005)

Q6.

A typical example of cross pollination is: [IOM 2001, 2009; BPKIHS 1997]

📅IOM 2001, 2009; BPKIHS 1997

Q7.

All are contrivances for cross - pollination in different plants except: [IOM 1998]

📅IOM 1998

Q8.

Xenogamy is called: [IOM 1998]

📅IOM 1998

Q9.

The medium of pollination in Vallisneria is: [IOM 1997]

📅IOM 1997

Q10.

The advantage of cross-fertilization when compared with self fertilization

Q11.

Hypohydrophily occurs in: [BPKIHS 2006]

📅BPKIHS 2006

Q12.

If pollen is transferred from anther of a flower to stigma of another flower of the same plant, it is called: [BPKIHS 2006]

📅BPKIHS 2006

Q13.

The monocot plumule is covered by: [IOM 2007]

📅IOM 2007

Q14.

Megasporophyll of gymnosperm is: [IOM 2007)

📅IOM 2007)

Q15.

Ovules symmetrical and straight with chalaza at the base and micropyle at the tip are called: [IOM 2006, BPKIHS 1996, MOE 2054]

📅IOM 2006, BPKIHS 1996, MOE 2054

Q16.

Primary endosperm nucleus is usually: [IOM 2004)

📅IOM 2004)

Q17.

Carpels of angiosperms are equivalent to: [IOM 2004]

📅IOM 2004

Q18.

Endosperm of maize is:[IOM 2002]

📅IOM 2002

Q19.

Double fertilization is seen in: [IOM 2001]

📅IOM 2001

Q20.

Embryo sac of the angiosperm before the fertilization is: [IOM 1997]

📅IOM 1997

Q21.

How many cells have undergone division to form 32 pollen grains? [IOM 1997]

📅IOM 1997

Q22.

Nuclei found at the centre of embryo sac is: [MOE]

📅MOE

Q23.

The point of junction of the integument and the nucellus is called the [IOM 1996]

📅IOM 1996

Q24.

35 meiotic division leads to the formation of how many seeds: [IOM 1996]

📅IOM 1996

Q25.

Parthenogenesis helps to form: [IOM 1999]

📅IOM 1999

Q26.

In angiosperm, embryo sac denotes: [BPKIHS 2000]

📅BPKIHS 2000

Q27.

If a diploid female plant is hybridized with a tetraploid male plant, then the endosperm is: [BPKIHS 2001]

📅BPKIHS 2001

Q28.

In 82% of angiosperm families, ovule is

Q29.

No. of chromosomes in the root of an angiospermic plant is 16. Then no. of chromosomes in its endosperm is: [BPKIHS 2002]

📅BPKIHS 2002

Q30.

Mode of reproduction resulting in the development of an embryo without the act of fertilization/meiosis [BPKIHS 2004]

📅BPKIHS 2004

Q31.

The entry of pollen tube through the micropyle is [BPKIHS 1996]

📅BPKIHS 1996

Q32.

Stalk of ovule is called

Q33.

Pollen grain is a [BPKIHS 1996]

📅BPKIHS 1996

Q34.

Pollen tube with two male nuclei is:

Q35.

Development of an unfertilized egg into embryo is: [BPKIHS 1996]

📅BPKIHS 1996

Q36.

Poppy seeds are dispersed by [BPKINS 1996]

📅BPKINS 1996

Q37.

Number of germ pores in a pollen is always [BPKIHS 1997]

📅BPKIHS 1997

Q38.

Insects pollinated pollen grains are [BPKIHS 1998]

📅BPKIHS 1998

Q39.

The pollination by wind is called: [MOE 2008, 2064]

📅MOE 2008, 2064

Q40.

The development of fruit without fertilization is: [MOE 2008, 2062, MOE 2011]

📅MOE 2008, 2062, MOE 2011

Q41.

Wind pollinated flowers are:[MOE 2063]

📅MOE 2063

Q42.

Winged seed is present in: [MOE 2063]

📅MOE 2063

Q43.

The process of forming new plants by cutting or grafting of any part of a plant is called: [MOE 2062]

📅MOE 2062

Q44.

In the seed micropyle is for entry of: [MOE 2003]

📅MOE 2003

Q45.

Linear tetrad cells are seen during development of: [MOE 2002]

📅MOE 2002

Q46.

Vivipary is a type of: [MOE 2000]

📅MOE 2000

Q47.

Endosperm of angiosperm develops after fertilization from: [MOE 2055)

📅MOE 2055)

Q48.

The first animals to serve as pollinators were: [IE 2007]

📅IE 2007

Q49.

A mature angiosperm ovule is: [IE 2001]

📅IE 2001

Q50.

Self pollination in a flower is dealt on the basis of [IE 2002]

📅IE 2002

Q51.

The number of gametes formed from AaBbCcDd is [IE 2005]

📅IE 2005

Q52.

Numerous, small, non sticky pollen and presence of feathery and non-sticky stigma is adapted for [BPKIHS - 2016]

📅BPKIHS - 2016

Q53.

Night blooming flowers are [BPKIHS - 2016, 2012]

📅BPKIHS - 2016, 2012

Q54.

Malacophily means pollination by [BPKIHS - 2015]

📅BPKIHS - 2015

Q55.

How many meiotic division is required to produce 100 pollen grains? [BPKIHS 2010]

📅BPKIHS 2010

Q56.

How many sperms are produced from 24 secondary spermatocyte [BPKIHS - 2010]

📅BPKIHS - 2010

Q57.

Formation of fruit from ovary without fertilization [BPKIHS - 2012]

📅BPKIHS - 2012

Q58.

Female gamete present in ovary [BPKIHS - 2012]

📅BPKIHS - 2012

Q59.

Apomixis involves development of embryo directly from: [BPKIHS- 2010]

📅BPKIHS- 2010

Q60.

Endosperm wall is formed from [BPKIHS - 2010]

📅BPKIHS - 2010

Q61.

Food is not stored in cotyledons and endosperm in [BPKIHS - 2010]

📅BPKIHS - 2010

Q62.

The point of attachment of ovule with funicle is called: [IOM-2014

📅IOM-2014

Q63.

In angiosperms, the female gametophyte is[IOM-2014]

📅IOM-2014

Q64.

Flowers which remain closed upto seed set is [IOM-2015]

📅IOM-2015

Q65.

Nutrition to the developing microspore is provided by [IOM-2016

📅IOM-2016

Q66.

Ornithophily is pollinated by [IOM-2016)

📅IOM-2016)

Q67.

Apomixis is development of a new plant [IOM-2013]

📅IOM-2013

Q68.

Grafting is not possible in monocotyledons because they [IOM-2013

📅IOM-2013

Q69.

The formation of fruit in absence of fertilization is [IOM-2013)

📅IOM-2013)

Q70.

An embryo sac of a flowering plant has [IOM-2013]

📅IOM-2013

Q71.

When pollination occurs between neighbouring flowers of the same plant, it is called [IOM-2013]

📅IOM-2013

Q72.

The edible part of apple and pear is [IOM-2013]

📅IOM-2013

Q73.

Milky water of green coconut is [IOM-2013]

📅IOM-2013

Q74.

Typical 8 nucleated embryo sac is of which type? [IOM-2012]

📅IOM-2012

Q75.

Which of the following is male gametophyte in higher plant? [IOM-2012]

📅IOM-2012

Q76.

A fruit developed without fertilization: [IOM-2012]

📅IOM-2012

Q77.

Entry of pollen tube through micropyle is [IOM-2015]

📅IOM-2015

Q78.

Double fertilization is a characteristic of [IOM-2015]

📅IOM-2015

Q79.

The development of zygote from egg cell without the act of fertilization as seen in many lower plants is called: [IOM-2015]

📅IOM-2015

Q80.

The unique character of floral parts which acts as a barrier to avoid self pollination and favors cross pollination is [IOM-2015]

📅IOM-2015

Q81.

Endosperm in angiosperm is [MOE 2014]

📅MOE 2014

Q82.

In capsela, the jacket layer of microsporangium is formed from [MOE 2014]

📅MOE 2014

Q83.

Which of the following develops into seed? [MOE 2014]

📅MOE 2014

Q84.

Which of the following statement is true? [MOE 2014]

📅MOE 2014

Q85.

Erect or straight form of ovule is referred as [MOE 2014]

📅MOE 2014

Q86.

The embryo sac develops from [MOE 2013]

📅MOE 2013

Q87.

Endospermic cells of an angiospermic plant are [MOE 2013]

📅MOE 2013

Q88.

When does meiosis occur in a flowering plant? [MOE 2013]

📅MOE 2013

Q89.

Which one is not a part of mature ovule? [MOE 2012]

📅MOE 2012

Q90.

Bisexual flower which never opens in its life span is [MOE 2012]

📅MOE 2012

Q91.

After fertilization, the seed coat develops from [MOE 2012]

📅MOE 2012

Q92.

Parthenogenesis is development of [MOE 2068]

📅MOE 2068

Q93.

Which is not a part of dicotyledonous embryo? [MOE 2068]

📅MOE 2068

Q94.

Ornithology is the study of [MOE 2068]

📅MOE 2068

Q95.

Formation of fruit without fertilization is called [MOE 2068]

📅MOE 2068

Q96.

A typical embryo sac of angiosperm has [MOE 2068]

📅MOE 2068

Q97.

In flowering plants, meiosis occur at the time of [MOE 2068]

📅MOE 2068

Q98.

Double fertilization is characteristics of [MOE 2068]

📅MOE 2068

Q99.

Which of the following plant shows polyembryony? [MOE 2010]

📅MOE 2010

Q100.

When the pollen from one flower is deposited on the stigma of another flower borne on different plant, the type of pollination is known as: [MOE 2010]

📅MOE 2010

Q101.

Megaspores develop from the cells of [MOE 2010)

📅MOE 2010)

Q102.

Double fertilization was first reported by [MOE 2010)

📅MOE 2010)

Q103.

Pollen tube develops from [MOE 2010)

📅MOE 2010)

Q104.

Which one is a mode of vegetative reproduction? [MOE 2068]

📅MOE 2068

📚

HIGH-YIELD RECALL

Table 1: Gymnosperm, Cycas & Pinus One-Liners

Fact	Answer
Naked-seeded plants	Gymnosperms
Reason for naked seed	Ovary absent
Living fossils	Cycas, Ginkgo, Metasequoia
Smallest gymnosperm	Zamia pygmaea
Xylem vessel	Absent except Gnetales
Gnetales examples	Gnetum, Ephedra, Welwitschia
Companion cells	Absent
Albuminous cells	Present
Sieve tubes	Absent
Sieve cells	Present
Pollination	Anemophilous
Ovule generally	Orthotropous
Pinus ovule	Anatropous
Gymnosperm endosperm	Haploid
Cycas stem	Caudex
Cycas root	Coralloid root
Coralloid root symbionts	Nostoc + Anabaena
Cycas fertilization	Zooidogamous
Female cone absent	Cycas
3-needled pine of Nepal	Pinus roxburghii
5-needled pine of Nepal	Pinus wallichiana
Pinus stem growth	Monopodial
Pinus branch types	Long shoot + dwarf shoot
Needles found on	Dwarf shoots
Pinus wood	Monoxylic + pycnoxylic
Pinus tracheids	Bordered pits
Pinus plant	Monoecious + autoecious
Female cone of Pinus	Modified inflorescence
Pinus ovules per ovuliferous scale	2
Pinus ovule	Unitegmic + anatropous
Pinus archegonia	2–5
Pinus neck cells	8
Pinus NCC	0
Winged pollen grain	Pinus
Winged seed	Moringa
Winged fruit	Hiptage, Shorea
Shower of sulphur	Yellow pollen release in Pinus
Pinus fertilization	Siphonogamous
Pinus fertilization time	11–15 months after pollination
Pinus seed maturity	After 3 years
Pinus germination	Epigeal
Cycas germination	Hypogeal
Pinus cotyledons	2–18

Table 1: Gymnosperm vs Angiosperm Homology

Table 1: Parts of Stamen

Table 1: Anther Structure

Table 1: Anther Wall Layers

Table 1: Types of Tapetum

Table 1: Tapetal Products

Table 1: Pollen Study Terms

Table 1: Pollen Grain

Table 1: Pollen Wall

Table 1: Cells of Pollen Grain

Table 1: Pollen Stage at Pollination

Table 1: Pollen Tube

Table 1: Special Pollen Points

Table 1: Carpel

Table 1: Parts of Ovule

Table 1: Types of Placentation

Table 1: Types of Ovule by Orientation

Table 1: Types of Ovule by Integument Number

Table 1: Ovule-associated Structures

Table 1: Mature Angiospermic Embryo Sac

Table 1: Polygonum Type Embryo Sac

Table 1: Types of Embryo Sac

Table 1: Self vs Cross Pollination

Table 1: Types of Allogamy

Table 1: Outbreeding Devices

Table 1: Pollination Agents

Table 1: Special Pollination Mechanisms

Table 1: Types of Pollen Tube Entry

Table 1: Double Fertilization

Table 1: Endosperm Difference

Table 1: Types of Endosperm

Table 1: Endospermic vs Non-endospermic Seeds

Table 1: Xenia vs Metaxenia

Table 1: Embryo Development

Table 1: Nutritive Tissues

Table 1: Types of Polyembryony

Table 1: Seed Coat Derivatives

Table 1: Seed Extremes

Table 1: Seed Types

Table 1: Epigeal vs Hypogeal Germination

Table 1: Types of Apomixis

Table 1: Related Reproductive Terms

Table 1: Main Fruit Types

Table 1: Dehiscent Fruits

Table 1: Capsule Dehiscence Types

Table 1: Indehiscent Dry Fruits

Table 1: Fleshy / Succulent Fruits

Table 1: Etaerio Fruits

Table 1: Composite Fruits

Table 1: Fruit Types of Important Families

Table 1: Angiosperm Reproduction One-Liners

Table 1: Gymnosperm, Cycas & Pinus One-Liners

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