Ch 08: Reproduction | Exam Fusion Prep

🔀 Asexual vs Sexual Reproduction

Feature	Asexual Reproduction	Sexual Reproduction
Parents needed	Single parent (or bisexual)	Two parents of different sex
Organisms	Simple organisms	Complex and developed organisms
Gametes	Absent (no gamete formation or fusion)	Present (gamete formation + fertilisation)
Offspring	Clone of parent (No variations)	Different from parents (Variations present)

Fission

Unicellular organisms

Fragmentation

Simple multicellular

Regeneration

Broken part → new organism

Budding

Bud on body

Spore Formation

Thick-walled spores

Vegetative Repro.

Root/Stem/Leaf

🦠 Types of Asexual Reproduction

1. Fission

Reproduction in unicellular organisms by amitotic cell division
Binary fission: 2 progenies formed
e.g. Amoeba, Bacteria, Leishmania, Paramecium
Multiple fission: Many progenies formed
e.g. Plasmodium (Malarial parasite)

2. Fragmentation

Simple multicellular organism breaks into 2+ segments
Each segment grows into complete organism
e.g. Spirogyra, Rhizopus, Ulothrix, Red algae

3. Regeneration

New offspring from any broken part of parent animal
e.g. Hydra, Planaria

4. Budding

Bud forms on body → develops into new organism
e.g. Hydra, Yeast

5. Spore Formation

Unicellular, thick-walled spores under unfavorable conditions
Germinate under favorable conditions
e.g. Chlamydomonas, Rhizopus, Mucor, Puccinia

Tissue Culture

Disease-free plants from plant tissue/parts in suitable culture medium in lab
Also called: In-vitro propagation / Micropropagation
Used for decorative and disease-free plants in less time

⚠ Exam Trap

Plasmodium = Multiple fission (malarial parasite). Hydra = Both budding AND regeneration. Yeast = Budding only. Leishmania = Binary fission (causes Kala-azar).

⚡ Quick Recall

Tissue culture = Micropropagation / In-vitro propagation. Disease-free plants banate hain laboratory mein.

🌿 Vegetative Reproduction

New offspring from vegetative parts: Roots, Stems and Leaves

Natural Vegetative Propagation

Part used	Examples
Stem	Potato, Sugarcane
Roots	Rosewood, Sweet potato
Leaf	Begonia, Bryophyllum

Artificial Vegetative Propagation

Cutting:
- Shoot cutting: Rose, Sugarcane, Banana
- Root cutting: Lemon, Orange
Layering: Apple, Pear, Lemon, Strawberry

⚠ Exam Trap

Potato = vegetative reproduction by Stem (not root!). Sweet potato = by Root. Bryophyllum = by Leaf. Ye three confuse karne wale examples hain!

🌸 Flower Structure

Flower = Condensed shoot, sexual organ of plant
Parts of flower:
- Calyx (green)
- Corolla (coloured)
- Androecium: Stamens = Male reproductive organ
- Gynoecium: Pistil/Carpel = Female reproductive organ

Bisexual / Monoecious Plants

Both male & female organs in same flower
e.g. Hibiscus, Pea, Rose, Sunflower, Tomato, Mango, Lily
Note: Maize has unisexual flowers

Dioecious Plants

Male and female flowers on separate plants
e.g. Papaya, Cucumber, Watermelon, Muskmelon

⚠ Exam Trap

Maize = Monoecious plant lekin unisexual flowers hote hain (male aur female alag alag flowers, same plant pe). Papaya = Dioecious (alag plants pe). Ye important distinction hai!

🔬 Double Fertilisation

Gametogenesis: Haploid pollen grains in anther (microsporogenesis) + Haploid embryo sac in ovule (megasporogenesis)

Male gamete (n) + Female gamete (n) = Zygote (2n) → Embryo

Male gamete (n) + Polar/Secondary nuclei (2n) = Endosperm (3n)

Ovule becomes:Seed Ovary becomes:Fruit

⚡ Quick Recall

Double fertilisation = unique to Angiosperms. Ek fertilisation → Embryo (2n). Doosra → Endosperm (3n = triploid). Endosperm food store karta hai seed mein.

🌼 Pollination

Transfer of pollen grain from anther to stigma of pistil

Self-Pollination

Autogamy: Within same bisexual flower
Geitonogamy: Between different flowers of same plant

Cross-Pollination

Between two different plants
Anemophily: By wind
e.g. Maize, Bamboo, Sugarcane
Hydrophily: By water
e.g. Vallisneria, Hydrilla
Entomophily: By insects
e.g. Salvia, Fig, Rose

⚠ Exam Trap

Anemophily = Wind pollination (Maize, Bamboo). Entomophily = Insect pollination (Rose, Fig). Hydrophily = Water pollination (Vallisneria). Teen -phily words yaad rakho!

⚡ Quick Recall

Autogamy = same flower | Geitonogamy = same plant different flower | Cross pollination = different plant. Geitonogamy genetically = self-pollination jaisi hai!

👨 Male Reproductive System

Testes: A pair of primary reproductive organs located in scrotum (outside abdominal cavity)
Produce male sex hormone Testosterone by Leydig cells
Produce haploid sperms through Spermatogenesis
Nutrition of sperms by Sertoli cells
Epididymis: Maturation of sperms
Vas deferens: A pair — transport sperm to seminal vesicles
Seminal vesicle → Urethra → Penis
Accessory glands: Prostate, Cowper's and perineal glands

⚠ Exam Trap

Testes = Scrotum mein hote hain (outside abdomen — temperature regulation ke liye). Leydig cells = Testosterone produce karte hain. Sertoli cells = Sperms ko nutrition dete hain. Dono different cells hain!

👩 Female Reproductive System

Ovaries: A pair of primary reproductive organs located in abdominal cavity
Secrete female sex hormones Oestrogen and Progesterone (by corpus luteum)
Produce haploid eggs through Oogenesis
Oviducts: A pair — connect ovaries to uterus
Uterus: Site of embryo development
Accessory glands: Bartholin's and perineal glands

⚖️ Male vs Female — Quick Compare

Feature	Male	Female
Primary organ	Testes (in scrotum)	Ovaries (in abdomen)
Hormone-producing cells	Leydig cells → Testosterone	Corpus luteum → Oestrogen, Progesterone
Gamete production	Spermatogenesis (haploid sperms)	Oogenesis (haploid eggs)
Nutrition support cells	Sertoli cells (for sperms)	—
Sperm/Egg maturation	Epididymis	Oviduct (carries egg)
Accessory glands	Prostate, Cowper's, Perineal	Bartholin's, Perineal

⚡ Quick Recall

Spermatogenesis = Male gamete formation | Oogenesis = Female gamete formation | Both produce haploid gametes via Meiosis. Fertilisation = Zygote (2n) formation.

🌱 Chapter 08 — Reproduction