In which organisms does spore formation occur as a mode of reproduction ?

Question

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Correct — B, Fungi. In school biology, 'spore formation' is the name of a specific mode of asexual reproduction, and the organism used to teach it is a fungus. The standard illustration is Rhizopus, the black bread mould: the fungal thread sends up an upright hypha tipped with a swollen sporangium, the sporangium matures and bursts, and the spores it scatters germinate into new mycelia wherever they meet moisture and food. The spores carry thick protective walls, which is why they survive drying and heat and travel on air currents, and it is why bread left uncovered develops mould without anyone introducing it. Two features of this option set point firmly at fungi. First, yeast is listed separately even though yeast is itself a fungus — and it is listed separately precisely because school texts teach yeast under budding, in which a small outgrowth swells on the parent cell and pinches off. Setting yeast against fungi in the same list is the setter signalling the budding-versus-spore-formation contrast, and it makes little sense unless the intended answer is fungi. Second, none of the other options is presented with its own characteristic mode; only fungi is. Honesty requires the caveat, though, because this question is loosely framed and the derivation carried only medium confidence. Ferns genuinely reproduce by spores, borne in sporangia clustered into sori on the underside of the frond, and many algae release motile zoospores. In strict biology more than one option can form spores, and a candidate who marked ferns has a real argument. The card argues fungi because that is where the syllabus places 'spore formation as a mode of reproduction' and because the deliberate pairing with yeast shows what the setter was contrasting.

Why the other options are wrong — (a) Not wrong in biology, but wrong for this question. Many algae do produce motile zoospores, yet the mode school texts attach to algae is fragmentation — Spirogyra breaking into pieces that each grow into a new filament — and it is fragmentation, not spore formation, that algae are used to illustrate.  (c) The most defensible of the wrong options, and the reason this item is loosely framed. Ferns are pteridophytes and really do reproduce by spores, produced in sporangia grouped into sori on the underside of the fronds. But that is taught under plant classification and alternation of generations, not under the chapter on modes of reproduction, where the spore-forming example is a fungus.  (d) A fungus, but the one fungus that is the exception. Yeast is the textbook example of budding, in which a bud appears on the parent cell, grows, and separates. Its separate appearance in this list, alongside 'Fungi', is the strongest clue in the question about what the setter intended.

Concept: Asexual reproduction produces offspring from a single parent without the fusion of gametes, and school biology teaches it as a set of named modes, each attached to a standard organism. Binary fission is Amoeba and Paramecium, where the parent cell divides into two. Multiple fission is Plasmodium. Budding is Hydra and yeast, where an outgrowth forms on the parent and detaches. Fragmentation is Spirogyra, where the filament breaks and each piece grows. Regeneration is Planaria. Vegetative propagation covers runners, tubers, bulbs and leaf buds in plants — Bryophyllum being the standard case. And spore formation is Rhizopus, the bread mould. Spores are single reproductive units enclosed in a resistant wall; because they are light, numerous and protected, they let an organism survive conditions that would kill the parent and colonise new ground when conditions improve. It is worth keeping two senses of the word apart: in fungi spores are the vehicle of asexual multiplication, while in ferns and mosses spores are one stage of an alternating life cycle in which a spore-producing generation succeeds a gamete-producing one.

State PCS 2024 Q58 — Science & Technology PYQ with Answer

State PCS 2024 Q58 — Science & Technology PYQ with Answer