Generated by claude-sonnet-4-6 · 2026-06-15 06:45 · grounding rag
Model Answer
(i) Spores are tiny, microscopic, single-celled reproductive structures produced by organisms like Rhizopus (bread mould). They are formed on sporangia (spore-containing structures) present at the tips of thread-like hyphae.
To overcome unfavourable conditions, spores develop a thick protective coat that resists heat, dryness, and other harsh conditions. When conditions become favourable, each spore germinates and grows into a new individual.
Organism: Rhizopus (bread mould) multiplies using spores.
(ii) Reasons for vegetative propagation:
- Plants that do not produce viable seeds (e.g., banana, rose) can still be propagated.
- It preserves the exact characteristics (traits) of the parent plant, ensuring uniform offspring.
Two methods of vegetative propagation:
- Cutting – a part of stem/leaf is cut and planted.
- Layering – a stem branch is bent to the soil and allowed to root before separation.
---
Explanation
- For (i), examiners expect: definition of spore, location (sporangia), survival mechanism (thick coat), and name of organism — all four points carry marks.
- For (ii), give exactly two reasons and two methods — listing more wastes time and earns no extra marks.
- Common named methods include cutting, layering, grafting, and tissue culture — any two are acceptable.
- Rhizopus is the standard NCERT example for spore formation; mention it by name.