Who was first to use the characteristics of vascular tissues in the classification of plants?

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Correct — C, A P de Condolle — the Swiss botanist Augustin Pyramus de Candolle (1778–1841), whose surname the booklet prints as 'de Condolle'. In his Théorie élémentaire de la botanique of 1813 he made the presence or absence of vascular tissue the primary division of the entire plant kingdom: Vasculares, plants that possess vascular bundles, which he equated with Cotyledoneae, against Cellulares, plants built of cells alone with no vascular tissue, which he equated with Acotyledoneae. Beneath that split he kept working with structure rather than with flower-counting: within Vasculares he separated Exogenae — the dicotyledons, whose stems thicken by adding new wood outside a cambium — from Endogenae, the monocotyledons, whose scattered bundles make the stem look as though it grows from within; and he ranged the dicot subclasses as Thalamiflorae, Calyciflorae, Corolliflorae and Monochlamydeae. That is the break the question is pointing at. The system then in possession of the field was Linnaeus's sexual system, which sorted plants by counting stamens and pistils — a fast artificial key that shelved wholly unrelated plants side by side. De Candolle argued instead for a natural method founded on the plant's own anatomy, and the same 1813 book coined the word taxonomy for the study of classification itself. He spent the rest of his life applying it in the Prodromus Systematis Naturalis Regni Vegetabilis, begun in 1824 and completed by his son Alphonse in 1873. The chronology then closes the question. Bentham and Hooker's Genera Plantarum came out in three volumes between 1862 and 1883; Engler and Prantl's Die Natürlichen Pflanzenfamilien was issued in parts between 1887 and 1915 — half a century and three-quarters of a century after 1813. Only one worker can be first, which is also why option (d) cannot stand. And de Candolle's division has outlived his system: today's split between vascular plants, the tracheophytes — ferns, gymnosperms and angiosperms — and the non-vascular bryophytes is his Vasculares and Cellulares under modern names.

Why the other options are wrong — (a) Adolf Engler (1844–1930) and Karl Prantl (1849–1893) produced Die Natürlichen Pflanzenfamilien in parts between 1887 and 1915 — about seventy-four years after de Candolle. It is also a different kind of system: the first widely adopted phylogenetic one, arranging families by presumed evolutionary advancement from simple to complex, and famously placing monocotyledons before dicotyledons. Its organising idea is evolution, not vascular anatomy.  (b) George Bentham (1800–1884) and Joseph Dalton Hooker (1817–1911), working at Kew, published Genera Plantarum in three volumes from 1862 to 1883, classifying some 97,205 species into 202 families and 7,569 genera — the largest and last of the great natural systems, and still the sequence many herbaria shelve by. But it is pre-Darwinian, built on overall floral and morphological affinity, and it appeared half a century after 1813.  (d) The stem asks who was first, and a superlative admits exactly one holder. Since de Candolle's 1813 work precedes Bentham and Hooker's 1862–83 and Engler and Prantl's 1887–1915 by decades, no combination of two or more names can satisfy 'first'. BPSC offers this catch-all option freely across the paper, and it is defensible only when two of the choices are independently true.

Concept: Systems of plant classification fall into three historical generations, and knowing which generation a name belongs to answers most questions of this type without any further memory. The first is artificial: Carl Linnaeus's sexual system, published in Species Plantarum in 1753, sorted plants on one or two arbitrary characters — the number and arrangement of stamens and pistils. It was quick to use and it gave botany binomial nomenclature, but it scattered relatives and united strangers. The second generation is natural: classification by the total resemblance of the plant, using as many characters as possible, on the assumption that overall affinity is real even if its cause is unknown. A. P. de Candolle's Théorie élémentaire de la botanique (1813) opened this phase and pushed it inward, to anatomy — his top-level cut is presence versus absence of vascular tissue — and Bentham and Hooker's Genera Plantarum (1862–1883) closed it as the most exhaustive natural system ever attempted. The third generation is phylogenetic: after Darwin's Origin of Species (1859) classification was expected to mirror descent, and Engler and Prantl (1887–1915), followed by Hutchinson and by others, arranged families from primitive to advanced. Modern practice has gone one step further again — the Angiosperm Phylogeny Group classification, first published in 1998 and now in its fourth revision, groups families by DNA sequence data rather than by appearance.

State PCS 2025 Q147 — Science & Technology PYQ with Answer

State PCS 2025 Q147 — Science & Technology PYQ with Answer