Apomixis is a type of reproduction that results in the development of a/an :

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Correct — option (1), "New organism without fusion of gametes". Apomixis is a form of asexual reproduction that mimics sexual reproduction. In flowering plants it means seed is set — a complete, viable, dispersible seed — without fertilisation ever having occurred. No male gamete fuses with an egg, so there is no meiotic recombination and no genetic contribution from a second parent, and the offspring is a genetic copy of the mother plant. The word itself carries the definition: 'a-' meaning without and 'mixis' meaning mingling, in contrast to amphimixis, the ordinary sexual process in which gametes do fuse. Option (1) states exactly this and is the credited answer. The reason apomixis attracts so much attention is agricultural, and it is worth understanding because it is the angle from which the topic is usually examined. Hybrid varieties are prized for hybrid vigour, but that vigour does not survive into the next generation: the F1 hybrid is heterozygous, its progeny segregate, and yield falls away. So a farmer growing hybrids must buy fresh seed every season rather than saving his own. If apomixis could be engineered into hybrid crops, the hybrid genotype would be passed on intact through seed, generation after generation, with no segregation at all — the vigour of a hybrid combined with the seed-saving economics of an open-pollinated variety. That is why apomixis is a standing research goal in plant breeding. Option (4), "Embryo from nucellus", is the strongest distractor and deserves care rather than dismissal. Development of an embryo directly from the nucellus is adventive or nucellar embryony, and it is genuinely one route by which apomixis occurs — it is what happens in many varieties of citrus and mango, where cells of the nucellus surrounding the embryo sac divide and produce additional embryos alongside the sexual one, giving seeds with several embryos, a condition called polyembryony. But nucellar embryony is a particular mechanism, not the definition of apomixis. Apomixis also occurs through routes that do not involve the nucellus at all, notably where the embryo develops from an unreduced cell of the embryo sac. The stem asks what apomixis as a type of reproduction results in, which calls for the general characterisation, and the general characterisation is a new organism formed without gamete fusion. This is a useful distinction to have practised. When one option gives the definition of a category and another gives an example of it, the definition answers a question phrased in general terms. The examiner is testing whether the candidate knows the boundary of the concept, not merely one instance falling inside it.

Why the other options are wrong — (b) Option (2) describes the exact opposite of apomixis. The fusion of gametes is syngamy, and reproduction proceeding through it is amphimixis — ordinary sexual reproduction, in which the zygote formed by fertilisation develops into the embryo. Apomixis is defined by the absence of that fusion, which is what the prefix 'apo-' signals. A candidate marking this option has read the stem as asking about seed formation in general rather than about the process the stem actually names.  (c) Option (3) describes something that is not a recognised developmental pathway. In an angiosperm seed the endosperm is nutritive tissue, formed in the double fertilisation process when a male gamete fuses with the polar nuclei, and its function is to nourish the developing embryo rather than to become one. Embryos arise from the egg cell in sexual reproduction, or from sporophytic tissue such as the nucellus or integuments in adventive embryony — not from the endosperm. This option pairs two real terms from the same page of the syllabus in a relation that does not exist.  (d) Option (4) names a real phenomenon that really is a form of apomixis — adventive or nucellar embryony, seen in citrus and mango, where nucellar cells develop into embryos and produce polyembryonic seeds. But it is one mechanism among several, not the definition. Apomixis also occurs without any involvement of the nucellus, for instance where an unreduced cell of the embryo sac develops into an embryo. Since the stem asks what apomixis as a type of reproduction results in, the general characterisation at option (1) is what is required; option (4) answers a narrower question that was not asked.

Concept: Apomixis is reproduction without gamete fusion that nonetheless produces seed — asexual reproduction wearing the costume of sexual reproduction. Because no meiotic recombination and no fertilisation occur, the resulting plants are genetically identical to the mother, so a population reproducing apomictically is a clone. The principal routes are two. In one, the embryo develops from a cell of the embryo sac that has not undergone reduction, so the embryo carries the maternal chromosome number unchanged; diplospory and apospory belong here. In the other, adventive or nucellar embryony, embryos arise directly from sporophytic tissue of the ovule — the nucellus or the integuments — outside the embryo sac altogether. The second route commonly gives polyembryony, more than one embryo in a single seed, and it is easily observed: sowing a seed of many citrus varieties yields several seedlings, most of them nucellar clones of the parent and one of sexual origin. Apomixis occurs naturally in several families, notably the grasses and the Asteraceae, and among cultivated plants in citrus and mango.

State PCS 2026 Q59 — Science & Technology PYQ with Answer

State PCS 2026 Q59 — Science & Technology PYQ with Answer