Part 7 — Applied & NEET-Level Complex Questions (Questions 151–175)

Part 7 — Applied & NEET-Level Complex Questions (Questions 151–175)

Q151. In a cross section of a dicot stem showing a ring of vascular bundles with interfascicular cambium, secondary growth is possible because:

A) Bundles are scattered
B) Interfascicular cambium connects fascicular cambia to form a continuous cambial ring that produces secondary xylem/phloem — allowing radial thickening
C) Epidermis becomes cambium only
D) Periderm becomes primary meristem
Answer: B
Explanation:
A) Scattered bundles = monocot.
B) Correct — fusion of fascicular and interfascicular cambia yields continuous cambium.
C/D) Not accurate.

Q152. Which of the following seedling types would you expect to show epigeal germination?

A) Hypogeal — cotyledons stay below ground (e.g., pea)
B) Epigeal — cotyledons are pushed above ground (e.g., Vicia?), actually pea exhibits epigeal? (Note: pea shows epigeal—be careful: many references: pea is epigeal. For clarity: Beans (Phaseolus) show epigeal; peas often epigeal as well.) — Epigeal germination pushes cotyledons above ground by elongation of hypocotyl.
C) None
D) Both cotyledons absent
Answer: B (epigeal)
Explanation:
A) Hypogeal is opposite.
B) Correct — epigeal involves hypocotyl elongation bringing cotyledons above soil.

Q153. Which of the following describes a perfoliate leaf?

A) Leaflets arranged around petiole only
B) Leaf base completely surrounds the stem so the stem seems to pass through the leaf (perfoliate), e.g., some species like Vitis? (classic example: Clematis, Bupleurum) — distinct morphological state where base is fused around stem
C) Leafless branch
D) Root modified as leaf
Answer: B
Explanation:
A/C/D) Not perfoliate.
B) Correct.

Q154. A cross-section of a lamina shows large air chambers (aerenchyma). This is adaptive for:

A) Desert plants only
B) Aquatic plants enabling buoyancy and internal gas exchange under submerged conditions
C) Plants in arctic only
D) Pollination exclusively
Answer: B
Explanation:
A/C/D) Not main functions.
B) Correct.

Q155. A plant species shows heterostyly (pin and thrum flowers). This adaptation promotes:

A) Selfing only
B) Outcrossing via promoting pollen transfer between complementary floral morphs and reducing self-fertilization (seen in Primula)
C) Wind pollination only
D) Asexual reproduction only
Answer: B
Explanation:
A/C/D) Not purpose.
B) Correct.

Q156. Which of the following floral characters is most directly associated with bird pollination (ornithophily)?

A) Small dull flowers only
B) Bright red tubular flowers with copious nectar and lack of scent adapted for birds with long beaks capable of hovering/perching (e.g., Hibiscus? Actually Hibiscus is bee-pollinated; bird-pollinated flowers like Heliconia, Erythrina, some Butea)
C) Underwater flowers only
D) Wind-pollinated catkins only
Answer: B
Explanation:
A/C/D) Not bird-pollination traits.
B) Correct.

Q157. Which of the following pairs correctly matches seed dispersal mode and morphological adaptation?

A) Wind dispersal — heavy fleshy fruits only
B) Animal dispersal — fleshy, nutritious fruits or fleshy arils; wind dispersal — winged samaras or hairy pappus (dandelion); water dispersal — buoyant fruits with air cavities (coconut)
C) No relation between form and dispersal
D) Insects disperse seeds by ingestion only
Answer: B
Explanation:
A/C/D) Incorrect.
B) Correct.

Q158. Anemophilous flowers typically have:

A) Large, colorful petals and nectar to attract pollinators
B) Reduced perianth, exposed stamens and stigmas, abundant light small pollen grains adapted for wind dispersal (e.g., grasses, many trees), and no nectar/scent attraction
C) Sticky nectaries only
D) Velcro-like structures only
Answer: B
Explanation:
A/C/D) Traits of biotic pollination.
B) Correct.

Q159. In double fertilization, the polar nuclei fuse with a male gamete to form:

A) Diploid zygote only
B) Triploid endosperm nucleus that gives rise to nutritive tissue for embryo in angiosperms
C) Seed coat only
D) Fruit wall only
Answer: B
Explanation:
A) Zygote formed by egg + male gamete (syngamy).
B) Correct.
C/D) Not endosperm origin.

Q160. Which of the following structural modifications is commonly seen in climbing plants to reduce self-shading and reach light?

A) Thick trunk only
B) Tendrils, twining stems, hooks, adventitious roots that cling to host, and flat epiphytic stems depending on mechanism of climbing — morphological and physiological strategies to reach light with minimal investment in supportive tissues
C) No leaves only
D) Root modification only
Answer: B
Explanation:
A/C/D) Not main climbing adaptations.
B) Correct.

Q161. In a flower, adnation refers to:

A) Fusion of similar organs only
B) Fusion of dissimilar organs (e.g., stamens fused to corolla) — adnation is fusion between members of different whorls
C) Absence of floral parts
D) None of the above
Answer: B
Explanation:
A) Connation is fusion among similar organs.
B) Correct.
C/D) Incorrect.

Q162. If a berry like tomato has a superior ovary and pericarp indistinctly differentiated, which tissue becomes the fleshy edible part?

A) Pericarp (previously ovary wall) becomes fleshy; in tomato mesocarp & endocarp form part of edible tissue — accessory tissue may also contribute in some fruits
B) Seed coat only
C) Stamen only
D) Petiole only
Answer: A
Explanation:
A) Correct.
B/C/D) Not edible flesh origin.

Q163. In xylem, the difference between tracheids and vessels is that vessels:

A) Are narrow and elongated only
B) Are composed of vessel elements with perforation plates forming continuous tubes, are more efficient in water conduction in angiosperms while tracheids serve both conduction and support, present in gymnosperms and angiosperms (except Gnetales have vessels)
C) Do photosynthesis only
D) Are only in roots
Answer: B
Explanation:
A/C/D) Not accurate.
B) Correct.

Q164. Hypanthium (floral cup) formation where floral parts are united to a cup-like structure indicates:

A) Epigyny only
B) Perigyny (perigynous flowers) where petals, sepals and stamens are attached to a hypanthium surrounding superior ovary producing half-inferior appearance in some cases
C) Hypogyny only
D) No floral fusion
Answer: B
Explanation:
A/C) Different ovary position contexts.
B) Correct.

Q165. In wind-pollinated tree species like many temperate trees, the flowers are often:

A) Showy and brightly colored for birds
B) Small, inconspicuous, producing large amounts of pollen and exposed stamens and stigmas for efficient wind dispersal (catkins in willows, birches)
C) Aquatic only
D) Succulent and juicy
Answer: B
Explanation:
A/C/D) Not wind pollination traits.
B) Correct.

Q166. Fruit set without fertilization (parthenocarpy) results in:

A) Seeded fruit only
B) Seedless fruits (e.g., seedless grapes and bananas) produced via parthenocarpy or stenospermocarpy techniques useful in horticulture
C) No fruit at all
D) Only dry fruits
Answer: B
Explanation:
A/C/D) Not definitions.
B) Correct.

Q167. Which of the following is true about axillary bud development?

A) Axillary buds arise in leaf axils and can form branches, flowers or be dormant; apical dominance mediated by auxin suppresses outgrowth of axillary buds while cytokinins promote branching
B) Axillary buds are only reproductive always
C) Axillary buds form only roots
D) Axillary buds absent in all plants
Answer: A
Explanation:
A) Correct.
B/C/D) False.

Q168. Which of the following is the best description of a follicle fruit?

A) A fruit derived from syncarpous gynoecium splitting along two sutures
B) A dry dehiscent fruit formed from single carpel splitting along one suture (e.g., Magnolia, some Ranunculaceae)
C) A fleshy aggregate only
D) Multiple fruit of many flowers
Answer: B
Explanation:
A/C/D) Not follicle.
B) Correct.

Q169. Pollen grains with porate or colpate apertures are typical of:

A) Gymnosperms only with no apertures always
B) Angiosperms (especially dicots have tricolpate pollen; monocots often monosulcate) and pollen aperture types aid in identification and relate to pollen germination patterns
C) Fungi only
D) Algae only
Answer: B
Explanation:
A/C/D) Not accurate.
B) Correct.

Q170. A flower with superior ovary and free petals is described as:

A) Epigynous and sympetalous
B) Hypogynous and polypetalous (e.g., mustard) where floral parts are attached below ovary and petals are free, not fused
C) Perigynous only
D) None
Answer: B
Explanation:
A) Epigynous = inferior ovary.
B) Correct.
C/D) Other conditions.

Q171. In vegetative propagation by cutting, adventitious root formation is induced by:

A) Application of auxins like IAA/IBA to promote root initiation from stem cuttings and favorable humidity/temperature conditions
B) Cold water only
C) High levels of cytokinin exclusively
D) Direct sunlight only
Answer: A
Explanation:
B/C/D) Not main hormonal triggers.
A) Correct.

Q172. Which adaptation minimizes self-pollination in many flowering plants?

A) Temporal separation of male and female phases (dichogamy) such as protandry/protogyny, spatial separation (herkogamy), heterostyly, self-incompatibility mechanisms — all reduce selfing to promote outcrossing
B) Always simultaneous release and receptive phases only
C) No adaptation at all
D) None of the above
Answer: A
Explanation:
A) Correct.
B/C/D) Not promoting outcrossing.

Q173. A botanist finds a fruit formed by fusion of many flowers of an inflorescence into a single fruiting structure (e.g., pineapple). This is called a:

A) Aggregate fruit
B) Multiple (or composite) fruit — results from inflorescence of many flowers (e.g., pineapple, fig)
C) Simple fruit only
D) Accessory fruit only
Answer: B
Explanation:
A) Aggregate = many ovaries of a single flower.
B) Correct.
C/D) Different.

Q174. A grass (Poaceae) flower is adapted for wind pollination. Which of the following is not typical?

A) Reduced perianth lacking colorful petals
B) Large showy scented corolla attracting insects
C) Long feathery stigmas and exerted stamens producing abundant lightweight pollen
D) Small flowers arranged in spikelets forming inflorescences suited for wind dispersal
Answer: B
Explanation:
A/C/D) Typical of anemophilous grasses.
B) Not typical.

Q175. The formation of a hypanthium (floral tube) and its fusion with the ovary is most closely associated with which ovary position?

A) Hypanthium formation can result in perigynous flowers with half-inferior ovary when hypanthium surrounds but not fused to ovary; if fused it can give appearance of inferior ovary (epigyny) — correct association depends on fusion and ovary position in each species
B) Hypogyny only always
C) No relation to ovary position
D) Root structure only
Answer: A (explanatory nuance)
Explanation:
A) Correctly notes that hypanthium plus fusion relationships determine apparent ovary position; perigyny vs epigyny distinctions depend on whether hypanthium is free or fused.
B/C/D) Oversimplifications or incorrect.

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