UPHESC Assistant Professor Botany 2025 PYQs

Concept: Each term is directly defined by the item in the same row.

1. Sphingosine – 18-carbon amino alcohol (2-amino-4-octadecene-1,3-diol) with a trans double bond; backbone of sphingolipids (a – i).
2. PHY genes (PHYA–PHYE in Arabidopsis) encode the phytochrome apoprotein, which binds the chromophore phytochromobilin (b – ii).
3. PCD – programmed cell death, i.e. apoptosis (c – iii).
4. MYB proteins – a large family of transcription factors (e.g. regulate anthocyanin, trichomes) (d – iv).

Short trick: Here the lists are already in order: i-ii-iii-iv.

Concept: Somatic embryos (or shoot buds) encapsulated in a sodium alginate gel hardened in CaCl₂ (Ca-alginate beads) form 'synthetic seeds' (Murashige, 1977).

1. They are called synthetic seeds, artificial seeds, or encapsulated seeds/somatic embryos.
2. 'Closed seeds' is not a term used for them.

Short trick: Syn-seed = somatic embryo + alginate coat.

Concept: Somaclonal variation (Larkin & Scowcroft, 1981) = genetic variation arising in plants regenerated from tissue culture.

1. Bio-13 – high-oil citronella (Cymbopogon winterianus) variety from somaclonal variation (CIMAP).
2. Super tomatoes (high solids) and low-oxalate lines are reported somaclonal variants.
3. Topato/Pomato was produced by protoplast fusion of potato and tomato (Melchers, 1978) – a somatic hybrid, not a somaclonal variant.

Short trick: Somaclone = variant of ONE plant from culture; Pomato/Topato = fusion of TWO species.

Concept: Whittaker (1972, 1977) defined inventory and differentiation diversities at increasing scales.

1. Point diversity – within a single sample/quadrat (a – i).
2. Alpha – within a habitat/community (b – ii).
3. Beta – turnover between two habitats/communities along a gradient (c – iii).
4. Delta – differentiation between two landscapes (d – iv); gamma = landscape-level inventory, epsilon = regional.

Short trick: Point → Alpha → Beta → (Gamma) → Delta: small scale to large.

Concept: Whether a mutation is seen depends on ploidy and dominance.

1. (A) ✔ – a monoploid/haploid has one allele per gene, so both dominant and recessive mutations are expressed at once (hence haploids are used in mutation breeding).
2. (B) ✔ in the textbook sense – a recessive mutation in a diploid shows only when homozygous (or hemizygous for X-linked genes).
3. (C) ✘ – recessive alleles are masked in the heterozygote.
4. (D) ✔ – an X-linked recessive lethal kills hemizygous males, so the progeny show a 2 ♀ : 1 ♂ ratio (basis of Muller's ClB test).
5. As printed, at least (A) and (D) – and (B) – are correct, so no single option can be chosen; the question is treated as a bonus.

Short trick: Haploid shows all; diploid hides recessives; X-linked lethal tilts sex ratio.

Concept: Pentoxylales (Sahni, 1948) are Jurassic fossil gymnosperms from Nipania, Rajmahal Hills; each organ has its own form-genus.

1. Stems: Pentoxylon sahnii and Nipanioxylon guptai (Srivastava) – polystelic. In Nipanioxylon the stem has one stele at the base and apex but 5–7 steles in between – the only stem genus among the options.
2. Nipaniophyllum raoi – the strap-shaped leaf.
3. Carnoconites (printed 'Cornoconites') laxum – female (seed-bearing) cone.
4. Sahnia nipaniensis – male cone.

Short trick: Pentoxylales kit: -xylon = stem, -phyllum = leaf, Carnoconites = ♀ cone, Sahnia = ♂ cone.

Concept: Cycads range from tree-like Dioon spinulosum (up to 15–16 m, leaves 1.5–2 m) to dwarf Zamia.

1. Zamia pygmaea (Cuba) is the smallest cycad – tuberous stem ~2–3 cm and leaves only about 10–25 cm long.
2. Z. pumila and Z. floridana (coontie) have leaves 0.3–1 m long.
3. Dioon spinulosum has some of the largest leaves.

Short trick: Pygmy = smallest: Zamia pygmaea.

Concept: The Convention on Biological Diversity was opened at the Rio Earth Summit (1992) and came into force in 1993.

1. Article 1 lists three objectives: (1) conservation of biological diversity, (2) sustainable use of its components, (3) fair and equitable sharing of benefits from genetic resources.
2. Options A–C each miss one objective; only D has all three.
3. Supporting protocols: Cartagena (biosafety, 2000) and Nagoya (access & benefit-sharing, 2010).

Short trick: CBD = C-S-B: Conserve, Sustainably use, Benefit-share.

Concept: Several hypotheses explain why alien species become invasive.

1. Statement I ✔ – Empty niche hypothesis (Elton): an invader succeeds by using resources/niches left unused by native species.
2. Statement II ✘ – Novel weapons hypothesis (Callaway & Ridenour, 2004) says invaders win through new allelochemicals to which natives are not adapted (e.g. Centaurea, Parthenium).
3. 'Release from natural enemies' is the Enemy Release Hypothesis (Keane & Crawley, 2002), not the novel weapons hypothesis.

Short trick: Empty niche = unused space; Novel weapons = allelopathy; ERH = no enemies.

Concept: Brundtland Report (Our Common Future, 1987): development that meets present needs without compromising the ability of future generations to meet theirs.

1. It rests on three interdependent pillars – economic growth, social equity/inclusion and environmental protection (the 'triple bottom line': profit, people, planet).
2. Peace and security are goals (e.g. SDG 16) but are not the three defining pillars.

Short trick: 3 Ps – Profit (economic), People (social), Planet (environment).

Concept: Verhulst–Pearl logistic model: $\frac{dN}{dt}=rN(1-\frac{N}{K})$ gives an S-shaped (sigmoid) curve.

1. a ✘ – at N = K the bracket is 0, so growth rate = 0; the maximum rate is at N = K/2 (inflection point).
2. b ✔ – as N → K, (1 − N/K) → 0, so growth slows.
3. c ✔ – if N > K, (1 − N/K) is negative → dN/dt < 0, population falls back to K.
4. d ✔ – K is the carrying capacity.

Short trick: Logistic: fastest at K/2, zero at K, negative above K.

Concept: Pathogen recognition (PAMP/effector) triggers an ion flux and, within minutes, an oxidative burst.

1. NADPH oxidase (RBOH) at the plasma membrane rapidly produces superoxide and H₂O₂ (ROS) – the earliest defence event.
2. ROS directly kill microbes, cross-link cell walls and act as signals for the later hypersensitive response (localized cell death, hours).
3. Hormonal (SA, JA, ET) signalling and chromatin remodelling for defence-gene expression follow later.

Short trick: Order: recognition → Ca²⁺/ion flux → ROS burst → HR → hormones/SAR.

Concept: SAR is long-lasting, broad-spectrum resistance that develops in uninfected parts after a local infection.

1. It needs salicylic acid (SA) accumulation; SA (with mobile signals like methyl salicylate, pipecolic acid) acts through NPR1 to induce PR (pathogenesis-related) proteins.
2. Plants unable to accumulate SA (NahG transgenics) cannot develop SAR.
3. Jasmonic acid + ethylene mediate ISR (induced systemic resistance by rhizobacteria); ABA and GA are not SAR inducers.

Short trick: SAR – SA; ISR – JA/ET.

Concept: Chloroplasts (and mitochondria) are double-membrane, semi-autonomous organelles.

1. They have their own circular DNA, 70S ribosomes and divide by fission – 'semi-autonomous' (printed 'semi-autosomal') because many proteins are still nuclear-encoded.
2. In most angiosperms plastids pass only through the egg cytoplasm → maternal (cytoplasmic) inheritance, e.g. leaf variegation in Mirabilis jalapa (Correns).
3. Lysosomes, peroxisomes and endosomes are single-membrane and lack DNA.

Short trick: Double membrane + own DNA + maternal = chloroplast/mitochondrion.

Concept: Micropropagation = rapid clonal multiplication of plants in vitro.

1. b ✔ – done in controlled culture rooms, so plantlets are produced all year, independent of season.
2. c ✔ – a very small explant (shoot tip, node, meristem) can give thousands of plants.
3. d ✔ – meristem-tip culture gives virus/disease-free propagules (e.g. potato, banana, sugarcane).
4. a ✘ – the aim is true-to-type clones; generating a range of variability (somaclonal variation) is a drawback for micropropagation.

Short trick: Micropropagation = Many, Uniform, Clean, All-year.

Concept: The statements are really the purposes/uses of producing haploids (anther/pollen culture, Guha & Maheshwari 1964).

1. a ✔ – a haploid has one allele per gene, so recessive mutants are seen and screened directly.
2. b ✔ – doubling haploids with colchicine gives completely homozygous (doubled-haploid) diploids in one generation.
3. c ✔ – these pure lines speed up breeding of disease-resistant, superior varieties.
4. d ✘ – haploids are not made to induce polyploidy; doubling only restores the diploid level.

Short trick: Haploids → see recessives → double → pure lines → new varieties.

Concept: A trichogyne is a receptive hair-like tip of the female sex organ.

1. (A) ✘ – it occurs on the ascogonium of Ascomycota (e.g. Neurospora, Pyronema, Ascobolus) and on the carpogonium of red algae (Polysiphonia, Batrachospermum) – not in Basidiomycota, which lack sex organs (somatogamy, spermatization in rusts on receptive hyphae).
2. (R) ✔ – its function is to receive the male nucleus/spermatium (or contact the antheridium) and conduct it to the female cell.

Short trick: Trichogyne → Ascomycetes & red algae; Basidiomycetes have no sex organs.

Concept: Downy mildews (Peronosporales, Oomycota) are obligate biotrophs.

1. (A) ✔ – Peronospora destructor causes downy mildew of onion (pale, elongated lesions with violet-grey sporulation).
2. (R) ✘ – like other downy mildews it cannot be grown on artificial culture media; it is maintained only on living host plants.

Short trick: Downy mildews, powdery mildews and rusts = obligate parasites – no lab culture.

Concept: Match botanical names with popular names.

1. Nigella damascena – love-in-a-mist (flower sits in a mist of feathery bracts) (a – ii).
2. Leucaena leucophloea (= Acacia leucophloea) – white-barked 'popinac' / safed babool (b – iii).
3. Helichrysum bracteatum – strawflower/paper flower (papery, everlasting bracts) (c – iv).
4. Cestrum nocturnum – night jasmine, raat-ki-rani (night-scented) (d – i).

Short trick: Nocturnum = night; bracteatum = papery bracts; Nigella = mist.

Concept: Locate each inhibitor on the mitochondrial ETC/ATP synthase.

1. Cyanide – binds Fe³⁺ of cytochrome a₃, inhibiting cytochrome oxidase (Complex IV) (a – IV).
2. Aurovertin (printed 'Auravertin') – binds the β-subunits of F₁ of ATP synthase (b – III).
3. Valinomycin – a K⁺ ionophore that dissipates the membrane potential (c – I).
4. Antimycin A – blocks Complex III (cyt b → cyt c₁/c, Q_i site) (d – II).

Short trick: CN – Complex IV; Antimycin – III; Aurovertin/Oligomycin – ATP synthase; Valinomycin – K⁺.