SEXUAL REPRODUCTION IN FLOWERING PLANTS
1. FLOWER (4 WHORLS) 2. ANDROECIUM (STAMEN) 3. MICROS PORANGIUM (T.S.)
1. Calyx (Sepals) → Protects bud Stigma • Anther → Bilobed 1. Epidermis → Protective
2. Corolla (Petals) → Attract pollinators
Each lobe has 2 theca 2. Endothecium Helps
Style → 4 microsporangia in dehiscence
3. Androeciun (Male part) (pollen sacs) 3. Middle layers →3-4
Petal
Stamen • Filament → Long slender stalk
layers of parenchyma
4. Gynoecium (Female part) Anther
2 theca, (©) → 4. Tapetum → Nutritive
→ Pistil / Carpel -Filament layer, provides
4 microsporangia nourishment, produces
Bisexual flower → Sepal Types of Anther
Callase enzyme
• Dithecous → 2 theca (common) Sporopollenin precursors
Hibiscus (China rose)
Ovary • Monothecous →1theca
(e.g., Malvaceae)
4. MICROSPOROGENESIS (PoLLEN FORMATION) 5. POLLEN GRAIN 6. FACTS ABOUT POLLEN
Meiosis Meiosis I Exine → Made of 1. Viability → How long pollen can survive
Sporogenous,
tissue
(2n) sporopollenin (very • Wheat & rice → ~30 min
PMC resistant)
Rosaceae, Lequminosae, Solanaceat → months
Tetrad Intine Made of 2. Allergies → Parthenium (carrot grass) pollen
(4 haploid cells) cellulose & pectin → Allergy, → Bronchitis
Germ pore → Site of
. PMC (2n) → Meiosis I→ 2 cells (n) pollen tube emergence 3. Supplements → Tablet, Syrup
→ In performance
• Meiosis II → 4 haploid cels (tetrad) At maturity (2-celled stage)
Vegetative cell → Forms pollen tube
• Tetrad surrounded by callose wall 4. Cryopreservation -→ (-196°C) → Liquid N,
Generative cell → Forms male gametes → Pollen preserved for future use.
7. GYNOECIUM (PISTIL) 8. TYPES OF GYNOECIUM 9. OvULE (MEGASPORANGIUM)
Funicle → Stalk
Stigma -→ Landing platform
for pollen grain Monocarpellary Multicarpellary Hilum Attachment point
(Single carpel) (Many carpets)
Integuments → Protective layers
Style → Long, slender,
supports pollen tube Apocarpous Syncarpous - Micropyle → Opening
Ovary → Contains ovule (Carpels fre) (Carpals fused) Nucellus→ Nutritive tissue
MMC (2n) → Megaspore
mother cell
10. MEGASPOROGENESIS 11. EMBRYO SAC (FEMALE GAMETOPHYTE) 12. FERTILIZATION (DoUBLE FERTILIZATION)
MMC Meiosis I Meiosis II (n) Pollen tube enters
(n)3de
Antipodals (Chalazal end) 7-celled, through micropyle
(2n) 8-nucleate
n
19enerate - 2 Polar nuclei (Central cell) One male gamete (n) + Egg (n)
embryo sac
n
→ Zygote (2n)
• 4 megaspores formed Synergids .3 Antipodals
.
3 degenerate 1 functionat -1 Egg celu (Micropyle end) 2 Synargids Second male gamete (n) + Polar
•
.
1 functional megaspore megaspore • 1 Egg cell nuclei (ntn) → Primary endosperm
Micropyle end 2 Polar nuclei nucleus (3n)
.
(in central cell)
13. PosT FERTILIZATION CHANGES 14. TYPES OF FRUITS B. Based on nature
• Zygote -→ Embryo A. Based on development (() Fleshy fruits → e.g., Mango, Tomato
• Primary endosperm nucleus (3n) → Endosperm () True fruit → Develops from ovary (ü) Dry fruits
e.g, Mango, Tomato
• Integuments → Seed coat (a) Dehiscent → Open at maturity
• Ovule → Seed (ü) False fruit → Develops from e.g., Pea Ladyfinger
other parts (b) Indehiscent Do not open at
• Ovary→ Fruit
e.g., Apple, Cashew, Strawberry maturity e.g., Wheat, Maize
COMPLETE FLOW OF SEXUAL REPRODUCTION
Flower (Stamen) Anther PMC Meiosis Pollen grain Pollination Pollen tube Double
Zygote (2n) SeedFruit
(Microsporangium) (2n) (n) enters ovule fertilization
Endosperm (3n)
n = Haploid (Gametes) 2n = Diploid (Zygote, PMC, MMC) 3n = Triploid (Primary endosperm nucleus)
1. FLOWER (4 WHORLS) 2. ANDROECIUM (STAMEN) 3. MICROS PORANGIUM (T.S.)
1. Calyx (Sepals) → Protects bud Stigma • Anther → Bilobed 1. Epidermis → Protective
2. Corolla (Petals) → Attract pollinators
Each lobe has 2 theca 2. Endothecium Helps
Style → 4 microsporangia in dehiscence
3. Androeciun (Male part) (pollen sacs) 3. Middle layers →3-4
Petal
Stamen • Filament → Long slender stalk
layers of parenchyma
4. Gynoecium (Female part) Anther
2 theca, (©) → 4. Tapetum → Nutritive
→ Pistil / Carpel -Filament layer, provides
4 microsporangia nourishment, produces
Bisexual flower → Sepal Types of Anther
Callase enzyme
• Dithecous → 2 theca (common) Sporopollenin precursors
Hibiscus (China rose)
Ovary • Monothecous →1theca
(e.g., Malvaceae)
4. MICROSPOROGENESIS (PoLLEN FORMATION) 5. POLLEN GRAIN 6. FACTS ABOUT POLLEN
Meiosis Meiosis I Exine → Made of 1. Viability → How long pollen can survive
Sporogenous,
tissue
(2n) sporopollenin (very • Wheat & rice → ~30 min
PMC resistant)
Rosaceae, Lequminosae, Solanaceat → months
Tetrad Intine Made of 2. Allergies → Parthenium (carrot grass) pollen
(4 haploid cells) cellulose & pectin → Allergy, → Bronchitis
Germ pore → Site of
. PMC (2n) → Meiosis I→ 2 cells (n) pollen tube emergence 3. Supplements → Tablet, Syrup
→ In performance
• Meiosis II → 4 haploid cels (tetrad) At maturity (2-celled stage)
Vegetative cell → Forms pollen tube
• Tetrad surrounded by callose wall 4. Cryopreservation -→ (-196°C) → Liquid N,
Generative cell → Forms male gametes → Pollen preserved for future use.
7. GYNOECIUM (PISTIL) 8. TYPES OF GYNOECIUM 9. OvULE (MEGASPORANGIUM)
Funicle → Stalk
Stigma -→ Landing platform
for pollen grain Monocarpellary Multicarpellary Hilum Attachment point
(Single carpel) (Many carpets)
Integuments → Protective layers
Style → Long, slender,
supports pollen tube Apocarpous Syncarpous - Micropyle → Opening
Ovary → Contains ovule (Carpels fre) (Carpals fused) Nucellus→ Nutritive tissue
MMC (2n) → Megaspore
mother cell
10. MEGASPOROGENESIS 11. EMBRYO SAC (FEMALE GAMETOPHYTE) 12. FERTILIZATION (DoUBLE FERTILIZATION)
MMC Meiosis I Meiosis II (n) Pollen tube enters
(n)3de
Antipodals (Chalazal end) 7-celled, through micropyle
(2n) 8-nucleate
n
19enerate - 2 Polar nuclei (Central cell) One male gamete (n) + Egg (n)
embryo sac
n
→ Zygote (2n)
• 4 megaspores formed Synergids .3 Antipodals
.
3 degenerate 1 functionat -1 Egg celu (Micropyle end) 2 Synargids Second male gamete (n) + Polar
•
.
1 functional megaspore megaspore • 1 Egg cell nuclei (ntn) → Primary endosperm
Micropyle end 2 Polar nuclei nucleus (3n)
.
(in central cell)
13. PosT FERTILIZATION CHANGES 14. TYPES OF FRUITS B. Based on nature
• Zygote -→ Embryo A. Based on development (() Fleshy fruits → e.g., Mango, Tomato
• Primary endosperm nucleus (3n) → Endosperm () True fruit → Develops from ovary (ü) Dry fruits
e.g, Mango, Tomato
• Integuments → Seed coat (a) Dehiscent → Open at maturity
• Ovule → Seed (ü) False fruit → Develops from e.g., Pea Ladyfinger
other parts (b) Indehiscent Do not open at
• Ovary→ Fruit
e.g., Apple, Cashew, Strawberry maturity e.g., Wheat, Maize
COMPLETE FLOW OF SEXUAL REPRODUCTION
Flower (Stamen) Anther PMC Meiosis Pollen grain Pollination Pollen tube Double
Zygote (2n) SeedFruit
(Microsporangium) (2n) (n) enters ovule fertilization
Endosperm (3n)
n = Haploid (Gametes) 2n = Diploid (Zygote, PMC, MMC) 3n = Triploid (Primary endosperm nucleus)
