Asexual Reproduction and Sexual Reproduction. --- TYPE 1: ASEXUAL REPRODUCTION Only ONE parent is involved. No gametes (sex cells) are needed. Offspring are genetically identical to the parent (called clones)
• Binary Fission — Parent splits into TWO equal parts
Amoeba, Bacteria (like Leishmania splits lengthwise) • Multiple Fission — Parent splits into MANY parts
Plasmodium (malaria parasite) • Budding — Small bud grows on parent, detaches and forms new organism
Hydra, Yeast • Fragmentation — Body breaks into pieces, each piece grows into new organism
Spirogyra (algae) • Regeneration — If an organism is cut, each part can grow into a full organism
Planaria, Starfish • Spore Formation — Organisms produce spores that germinate into new plants
Rhizopus (bread mould), Ferns, Mosses • Vegetative Propagation — New plants grow from roots, stems, or leaves
Potato (eyes/buds), Rose (stem cutting), Bryophyllum (leaf margin buds) --- TYPE 2: SEXUAL REPRODUCTION TWO parents are involved (male and female). Gametes are formed — male gamete (sperm) and female gamete (egg/ovum). Fertilisation joins them to form a zygote. The zygote develops into offspring
• Gamete = Sex cell (sperm or egg) • Fertilisation = Fusion of male and female gametes • Zygote = Cell formed after fertilisation • Internal Fertilisation — inside female body
Humans, Cow, Dog • External Fertilisation — outside female body, in water
Frog, Fish In Humans: • Puberty in girls: Around 10–12 years. Menstruation starts. • Puberty in boys: Around 13–14 years. • Menstrual cycle = 28 days • Gestation period (pregnancy) = 9 months (approximately 280 days) • Fertilisation occurs in the Fallopian tube • Implantation occurs in the Uterus In Plants (Flowers): • Stamen = Male part (produces pollen = male gamete) • Pistil/Carpel = Female part (contains ovule = female gamete) • Pollination = Transfer of pollen from stamen to pistil • Self-pollination = Same flower or same plant • Cross-pollination = Different plant of same species • Fertilisation in plants forms SEED. Ovary becomes FRUIT. ---
(
): Zygote = Male Gamete + Female Gamete Fruit = Fertilised Ovary | Seed = Fertilised Ovule ---
RRB Group D asks: Which organism reproduces by budding? / Where does fertilisation occur in humans? / What is the gestation period? / Vegetative propagation examples. --- SHORTCUT/TRICK: Trick 1 — Remember Budding: 'HY-dra and Yeast = HY-5 = Budding Brothers' Trick 2 — For plant parts: 'SiPF' = Stamen is Pollen (male), Pistil is Female ---
Question: Bread mould reproduces by
? Step 1: Bread mould = Rhizopus fungus Step 2: Rhizopus produces tiny spore sacs called sporangia Step 3: These sporangia burst and release spores into air Step 4: Spores germinate in suitable conditions to form new mould Answer: Spore Formation ---
Students confuse Regeneration with Fragmentation. Remember — Fragmentation means the organism naturally BREAKS apart (like Spirogyra). Regeneration means an organism can REGROW from a cut piece (like Planaria).
Also, many students think Yeast uses Binary Fission — it does NOT. Yeast uses BUDDING.
12graded MCQs · easy to hard · full solution & trap analysis