1. Pneumatophores are respiratory roots that grow vertically upwards (negatively geotropic) in:
Correct Answer: B (Rhizophora)
In halophytes like Rhizophora growing in swampy areas, oxygen is deficient in the soil; hence pneumatophores emerge vertically upwards with lenticels (pneumathodes) for gas exchange.
In halophytes like Rhizophora growing in swampy areas, oxygen is deficient in the soil; hence pneumatophores emerge vertically upwards with lenticels (pneumathodes) for gas exchange.
2. Stem thorns of Citrus and Bougainvillea are morphological modifications of:
Correct Answer: B (Axillary buds)
Axillary buds of stems get modified into woody, straight, pointed thorns in plants like Citrus and Bougainvillea to protect them from browsing herbivores.
Axillary buds of stems get modified into woody, straight, pointed thorns in plants like Citrus and Bougainvillea to protect them from browsing herbivores.
3. In Australian Acacia, the leaves are small and short-lived; the photosynthetic function is taken over by the expanded green:
Correct Answer: C (Petiole (Phyllode))
A phyllode is a modified petiole or rachis that becomes green, flattened, and leaf-like to carry out photosynthesis while reducing water loss.
A phyllode is a modified petiole or rachis that becomes green, flattened, and leaf-like to carry out photosynthesis while reducing water loss.
4. In a cymose inflorescence, the main axis terminates in a flower and the flowers open in:
Correct Answer: B (Basipetal succession)
In cymose inflorescence, growth of the peduncle is determinate (limited) because the apical meristem forms a flower. Subsequent younger flowers develop lower down the axis in a basipetal order.
In cymose inflorescence, growth of the peduncle is determinate (limited) because the apical meristem forms a flower. Subsequent younger flowers develop lower down the axis in a basipetal order.
5. Vexillary (papilionaceous) aestivation is characterized by which petal arrangement?
Correct Answer: B (One large standard (vexillum), two lateral wings (alae), and two fused anterior keels (carina))
Vexillary aestivation is a diagnostic feature of family Fabaceae (e.g., pea, bean) consisting of 1 posterior standard, 2 lateral wings, and 2 anterior fused keel petals.
Vexillary aestivation is a diagnostic feature of family Fabaceae (e.g., pea, bean) consisting of 1 posterior standard, 2 lateral wings, and 2 anterior fused keel petals.
6. In which of the following plants is the ovary epigynous (inferior ovary)?
Correct Answer: C (Guava, Cucumber, and ray florets of Sunflower)
In epigynous flowers, the thalamus completely encloses the ovary and fuses with it, while other floral parts arise above the ovary, making the ovary inferior.
In epigynous flowers, the thalamus completely encloses the ovary and fuses with it, while other floral parts arise above the ovary, making the ovary inferior.
7. Free-central placentation where ovules are borne on a central axis lacking septa is found in:
Correct Answer: A (Dianthus and Primula)
In free-central placentation (Dianthus, Primula), ovules develop on the central column and partition walls (septa) are completely absent.
In free-central placentation (Dianthus, Primula), ovules develop on the central column and partition walls (septa) are completely absent.
8. In a mango or coconut fruit (drupe), which layer forms the edible fleshy part and stony hard part respectively?
Correct Answer: B (Mesocarp (mango) and Endocarp (stony part of both))
Drupes develop from monocarpellary superior ovaries. In mango, the mesocarp is edible and fleshy, while the endocarp is stony and hard. In coconut, the mesocarp is fibrous.
Drupes develop from monocarpellary superior ovaries. In mango, the mesocarp is edible and fleshy, while the endocarp is stony and hard. In coconut, the mesocarp is fibrous.
9. In monocotyledonous seeds of grasses/maize, the single shield-shaped cotyledon is known as:
Correct Answer: C (Scutellum)
The single large, shield-shaped cotyledon situated towards the lateral side of the embryonal axis in grains (Poaceae/Gramineae) is the scutellum.
The single large, shield-shaped cotyledon situated towards the lateral side of the embryonal axis in grains (Poaceae/Gramineae) is the scutellum.
10. Diadelphous stamens with a (9) + 1 arrangement and marginal placentation are characteristic features of Family:
Correct Answer: B (Fabaceae (Leguminosae))
Fabaceae flowers typically possess 10 stamens in two bundles: 9 stamens fused by their filaments into a tube and 1 posterior stamen free [A(9)+1].
Fabaceae flowers typically possess 10 stamens in two bundles: 9 stamens fused by their filaments into a tube and 1 posterior stamen free [A(9)+1].
11. Tetradynamous stamens (4 inner long and 2 outer short) and a siliqua fruit with a false septum (replum) occur in:
Correct Answer: A (Cruciferae (Brassicaceae))
Brassicaceae (e.g., Brassica campestris / mustard) is characterized by a cruciform corolla, tetradynamous stamens (2+4), and a bicarpellary unilocular ovary that becomes bilocular due to a false septum (replum).
Brassicaceae (e.g., Brassica campestris / mustard) is characterized by a cruciform corolla, tetradynamous stamens (2+4), and a bicarpellary unilocular ovary that becomes bilocular due to a false septum (replum).
12. Monadelphous condition where staminal filaments fuse into a single central staminal tube surrounding the style is found in:
Correct Answer: C (China rose / Hibiscus (Malvaceae))
Family Malvaceae features monadelphous androecium, monothecous reniform (kidney-shaped) anthers, and an epicalyx.
Family Malvaceae features monadelphous androecium, monothecous reniform (kidney-shaped) anthers, and an epicalyx.
13. In Family Compositae (Asteraceae), the calyx is modified into persistent hairy structures for wind dispersal called:
Correct Answer: A (Pappus)
In Asteraceae (e.g., Sunflower, Tagetes), the calyx is reduced or modified into a ring of fine hairs or bristles called pappus, attached to a cypsela fruit.
In Asteraceae (e.g., Sunflower, Tagetes), the calyx is reduced or modified into a ring of fine hairs or bristles called pappus, attached to a cypsela fruit.
14. In Family Gramineae (Poaceae), the perianth is represented by reduced scale-like structures called:
Correct Answer: C (Lodicules)
In grass flowers (Poaceae), 2 (rarely 3) minute fleshy scale-like lodicules represent the reduced perianth that swell to push open the lemma and palea during anthesis.
In grass flowers (Poaceae), 2 (rarely 3) minute fleshy scale-like lodicules represent the reduced perianth that swell to push open the lemma and palea during anthesis.
15. Stilt roots supporting the lower nodes of tall slender stems are found in:
Correct Answer: A (Maize and Sugarcane)
Stilt roots are adventitious roots arising from lower nodes of the stem that grow obliquely downwards into the soil to provide mechanical support.
Stilt roots are adventitious roots arising from lower nodes of the stem that grow obliquely downwards into the soil to provide mechanical support.
16. Alternate phyllotaxy where a single leaf arises at each node in an alternating manner is seen in:
Correct Answer: A (China rose, Mustard, and Sunflower)
In alternate phyllotaxy, single leaves arise at successive nodes alternately (China rose, mustard, sunflower). Calotropis and guava show opposite phyllotaxy; Alstonia shows whorled phyllotaxy.
In alternate phyllotaxy, single leaves arise at successive nodes alternately (China rose, mustard, sunflower). Calotropis and guava show opposite phyllotaxy; Alstonia shows whorled phyllotaxy.
17. Stamens adhering to the perianth (tepals), termed “epiphyllous”, occur in:
Correct Answer: C (Lily (Liliaceae))
When stamens are attached to the petals, they are epipetalous (Brinjal). When attached to the perianth/tepals, they are epiphyllous or epitepalous (Lily).
When stamens are attached to the petals, they are epipetalous (Brinjal). When attached to the perianth/tepals, they are epiphyllous or epitepalous (Lily).
18. A false fruit (pseudocarp) is one where floral parts other than the ovary contribute to fruit formation, such as the fleshy thalamus in:
Correct Answer: A (Apple, Strawberry, and Cashew)
In apple, pear, strawberry, and cashew, the floral receptacle (thalamus) or pedicel enlarges to form the major edible portion of the fruit.
In apple, pear, strawberry, and cashew, the floral receptacle (thalamus) or pedicel enlarges to form the major edible portion of the fruit.
19. Collenchyma tissue provides mechanical support to growing parts (young stems and petioles) and has cell corners thickened with:
Correct Answer: B (Cellulose, Hemicellulose, and Pectin)
Collenchyma consists of living, elongated cells with uneven localized wall thickenings of cellulose, hemicellulose, and pectin at intercellular corners.
Collenchyma consists of living, elongated cells with uneven localized wall thickenings of cellulose, hemicellulose, and pectin at intercellular corners.
20. The gritty texture of the pulp of pear, guava, and sapota fruit is due to the presence of:
Correct Answer: C (Sclereids (stone cells))
Sclereids are spherical, oval, or cylindrical, highly thickened dead cells with narrow lumens (pits) found in fruit pulp, nutshells, and seed coats of legumes.
Sclereids are spherical, oval, or cylindrical, highly thickened dead cells with narrow lumens (pits) found in fruit pulp, nutshells, and seed coats of legumes.
21. In gymnosperms, xylem lacks true ________ and phloem lacks ________:
Correct Answer: B (Vessels; Sieve tubes and Companion cells)
Gymnosperms lack xylem vessels (conduction occurs via tracheids) and have albuminous cells and sieve cells instead of companion cells and sieve tubes.
Gymnosperms lack xylem vessels (conduction occurs via tracheids) and have albuminous cells and sieve cells instead of companion cells and sieve tubes.
22. Sieve tube elements are living cells that lack a nucleus at maturity; their function is controlled by the nucleus of:
Correct Answer: B (Companion cells)
Companion cells are specialized parenchymatous cells closely associated with sieve tube elements via pit fields in their common longitudinal walls.
Companion cells are specialized parenchymatous cells closely associated with sieve tube elements via pit fields in their common longitudinal walls.
23. Radial vascular bundles, where xylem and phloem are arranged on alternate radii, are found in:
Correct Answer: A (Roots)
In roots, xylem and phloem occur in separate bundles along alternating radii (radial). In stems and leaves, xylem and phloem lie along the same radius (conjoint).
In roots, xylem and phloem occur in separate bundles along alternating radii (radial). In stems and leaves, xylem and phloem lie along the same radius (conjoint).
24. Casparian strips present on the radial and tangential walls of root endodermal cells are made of an impermeable waxy substance called:
Correct Answer: B (Suberin)
The endodermis possesses Casparian strips made of suberin which block apoplastic water movement, forcing water to travel symplastically through cell membranes.
The endodermis possesses Casparian strips made of suberin which block apoplastic water movement, forcing water to travel symplastically through cell membranes.
25. Polyarch vascular bundles (more than 6 xylem bundles) and a large, well-developed pith are characteristic features of:
Correct Answer: B (Monocot root)
Dicot roots have 2 to 4 (rarely 6) xylem/phloem patches (diarch to tetrarch) with an inconspicuous pith. Monocot roots are polyarch (usually >6) with a large, prominent pith.
Dicot roots have 2 to 4 (rarely 6) xylem/phloem patches (diarch to tetrarch) with an inconspicuous pith. Monocot roots are polyarch (usually >6) with a large, prominent pith.
26. Scattered vascular bundles, each surrounded by a sclerenchymatous bundle sheath and lacking secondary growth, are found in:
Correct Answer: B (Monocot stem)
A monocot stem (e.g., maize) has numerous conjoint, collateral, closed vascular bundles scattered throughout ground parenchyma, each surrounded by a sclerenchymatous bundle sheath.
A monocot stem (e.g., maize) has numerous conjoint, collateral, closed vascular bundles scattered throughout ground parenchyma, each surrounded by a sclerenchymatous bundle sheath.
27. Bulliform (motor) cells present in the adaxial epidermis of grass leaves function to:
Correct Answer: B (Minimize water loss by leaf inward rolling under drought stress)
When bulliform cells absorb water, they are turgid and expose the leaf surface. When flaccid due to water deficit, they cause inward curling of leaves to curb water loss.
When bulliform cells absorb water, they are turgid and expose the leaf surface. When flaccid due to water deficit, they cause inward curling of leaves to curb water loss.
28. During secondary growth in a dicot stem, the interfascicular cambium develops from cells of:
Correct Answer: C (Medullary rays)
The intrafascicular cambium is primary, but the cells of medullary rays adjoining it dedifferentiate to form interfascicular cambium, completing the continuous vascular cambium ring.
The intrafascicular cambium is primary, but the cells of medullary rays adjoining it dedifferentiate to form interfascicular cambium, completing the continuous vascular cambium ring.
29. Heartwood (duramen) differs from sapwood (alburnum) because heartwood:
Correct Answer: A (Is dark, dead, filled with resins/tannins, contains tyloses, and provides mechanical support)
Heartwood is the non-conducting central core of older wood plugged by tyloses and impregnated with aromatic substances (tannins, oils, resins), rendering it decay-resistant and durable.
Heartwood is the non-conducting central core of older wood plugged by tyloses and impregnated with aromatic substances (tannins, oils, resins), rendering it decay-resistant and durable.
30. The cork cambium (Phellogen) cuts off cork (Phellem) towards the outside and ________ towards the inside:
Correct Answer: B (Secondary cortex (Phelloderm))
Phellogen (cork cambium) divides periclinally to produce phellem (cork) on the outer side and phelloderm (secondary cortex) on the inner side. Together they constitute the periderm.
Phellogen (cork cambium) divides periclinally to produce phellem (cork) on the outer side and phelloderm (secondary cortex) on the inner side. Together they constitute the periderm.
31. Lens-shaped openings in the bark of woody trees that permit gaseous exchange are called:
Correct Answer: C (Lenticels)
Phellogen produces loosely arranged parenchymatous complementary cells that rupture the epidermis to form aerating lens-shaped pores called lenticels.
Phellogen produces loosely arranged parenchymatous complementary cells that rupture the epidermis to form aerating lens-shaped pores called lenticels.
32. In a dorsiventral (dicot) leaf, the palisade mesophyll is situated:
Correct Answer: A (Towards the adaxial (upper) epidermis)
In dicot leaves, vertically elongated palisade parenchyma cells are packed densely beneath the adaxial (upper) surface, while spongy parenchyma lies towards the abaxial (lower) surface.
In dicot leaves, vertically elongated palisade parenchyma cells are packed densely beneath the adaxial (upper) surface, while spongy parenchyma lies towards the abaxial (lower) surface.
33. Simple squamous epithelium, with thin flattened cells and irregular boundaries, forms the lining of:
Correct Answer: B (Blood vessels (endothelium) and air sacs (alveoli) of lungs)
Simple squamous epithelium forms a delicate, thin diffusion barrier in alveoli and capillary endothelium.
Simple squamous epithelium forms a delicate, thin diffusion barrier in alveoli and capillary endothelium.
34. Ciliated columnar or cuboidal epithelium is specialized to move particles or mucus in a specific direction over:
Correct Answer: B (Bronchioles and Fallopian tubes (oviducts))
Cilia beat rhythmically to propel mucus out of bronchioles and propel ova down the oviduct towards the uterus.
Cilia beat rhythmically to propel mucus out of bronchioles and propel ova down the oviduct towards the uterus.
35. Which cell junction facilitates rapid cell-to-cell communication by connecting the cytoplasm of adjoining cells for ionic and small molecule transfer?
Correct Answer: C (Gap junctions)
Gap junctions contain tubular connexons that bridge cytoplasmic channels, enabling rapid electrical and chemical signaling across adjacent cells.
Gap junctions contain tubular connexons that bridge cytoplasmic channels, enabling rapid electrical and chemical signaling across adjacent cells.
36. Tendons and Ligaments are examples of dense regular connective tissue that attach:
Correct Answer: A (Skeletal muscle to bone (Tendon) and Bone to bone (Ligament))
Tendons are dense regular white fibrous cords connecting muscle to bone. Ligaments are dense regular yellow elastic bands uniting one bone to another.
Tendons are dense regular white fibrous cords connecting muscle to bone. Ligaments are dense regular yellow elastic bands uniting one bone to another.
37. Mast cells, fibroblasts, and macrophages are resident cellular components of:
Correct Answer: B (Areolar connective tissue)
Areolar tissue acts as a supporting framework beneath the skin, containing fibroblasts (secreting collagen/elastin), macrophages, and mast cells (secreting histamine, heparin, serotonin).
Areolar tissue acts as a supporting framework beneath the skin, containing fibroblasts (secreting collagen/elastin), macrophages, and mast cells (secreting histamine, heparin, serotonin).
38. Intercalated discs and communication junctions that allow cardiac muscle cells to contract as a synchronized unit (syncytium) are located in:
Correct Answer: C (Cardiac muscle)
Cardiac muscle cells are branched, uninucleated, and connected by dark transverse bands called intercalated discs with gap junctions.
Cardiac muscle cells are branched, uninucleated, and connected by dark transverse bands called intercalated discs with gap junctions.
39. Smooth muscle fibres found in the walls of internal organs (blood vessels, stomach, intestine) are:
Correct Answer: A (Involuntary, unstriated, and spindle-shaped (fusiform) with a central nucleus)
Smooth muscle fibers lack cross-striations, taper at both ends (fusiform), are uninucleate, and are regulated involuntarily by the autonomic nervous system.
Smooth muscle fibers lack cross-striations, taper at both ends (fusiform), are uninucleate, and are regulated involuntarily by the autonomic nervous system.
40. Which non-excitable cells make up more than one-half the volume of neural tissue in the human body and protect/support neurons?
Correct Answer: B (Neuroglial cells)
Neuroglia are supporting, non-conducting cells (astrocytes, oligodendrocytes, microglia, ependymal cells) constituting >50% of the nervous system.
Neuroglia are supporting, non-conducting cells (astrocytes, oligodendrocytes, microglia, ependymal cells) constituting >50% of the nervous system.
41. In Frog (Rana tigrina), cutaneous respiration through skin occurs:
Correct Answer: B (In water and also on land, as well as during hibernation and aestivation)
Frog skin is always kept moist by mucous glands, allowing dissolved oxygen to diffuse into subcutaneous capillaries in water, on land, and during winter/summer sleep.
Frog skin is always kept moist by mucous glands, allowing dissolved oxygen to diffuse into subcutaneous capillaries in water, on land, and during winter/summer sleep.
42. Male frogs can be distinguished morphologically from female frogs by the presence of:
Correct Answer: B (Vocal sacs beneath the throat and a copulatory (nuptial) pad on the first digit of forelimbs)
Sound-amplifying vocal sacs and copulatory pads (on the ventral side of the first forelimb digit) are male-specific secondary sexual traits used during amplexus.
Sound-amplifying vocal sacs and copulatory pads (on the ventral side of the first forelimb digit) are male-specific secondary sexual traits used during amplexus.
43. The triangular structure on the dorsal side of the frog heart that receives deoxygenated blood from the venae cavae is:
Correct Answer: B (Sinus venosus)
The frog heart has 3 chambers (2 atria, 1 ventricle). The sinus venosus is a thin-walled dorsal accessory chamber that collects venous blood and empties into the right atrium.
The frog heart has 3 chambers (2 atria, 1 ventricle). The sinus venosus is a thin-walled dorsal accessory chamber that collects venous blood and empties into the right atrium.
44. In frogs, the special venous connection between the liver and intestine, and between the kidneys and lower body parts, are called:
Correct Answer: A (Hepatic portal system and Renal portal system respectively)
Frogs possess both well-developed hepatic portal (gut to liver) and renal portal (hindlimbs/tail to kidney) venous vascular systems.
Frogs possess both well-developed hepatic portal (gut to liver) and renal portal (hindlimbs/tail to kidney) venous vascular systems.
45. What is the common chamber in the frog through which alimentary canal, urinary, and reproductive tracts open to the exterior?
Correct Answer: B (Cloaca)
The cloaca is a terminal common chamber that receives feces from the rectum, urine from ureters/urinary bladder, and gametes (sperms/ova) before exiting through the cloacal aperture.
The cloaca is a terminal common chamber that receives feces from the rectum, urine from ureters/urinary bladder, and gametes (sperms/ova) before exiting through the cloacal aperture.
46. In male frogs, 10-12 vasa efferentia arising from testes enter the kidney and open into:
Correct Answer: B (Bidder’s canal)
Vasa efferentia pass sperms into Bidder’s canal inside the kidney, which communicates with the urinogenital duct to carry both sperm and urine to the cloaca.
Vasa efferentia pass sperms into Bidder’s canal inside the kidney, which communicates with the urinogenital duct to carry both sperm and urine to the cloaca.
47. The excretory product of an adult frog and a tadpole larva are respectively:
Correct Answer: B (Urea (Ureotelic) and Ammonia (Ammoniotelic))
The aquatic tadpole larva excretes toxic ammonia (ammoniotelic), whereas the adult amphibious frog excretes urea (ureotelic) through mesonephric kidneys.
The aquatic tadpole larva excretes toxic ammonia (ammoniotelic), whereas the adult amphibious frog excretes urea (ureotelic) through mesonephric kidneys.
48. The tongue of a frog is adapted for prey capture because it is:
Correct Answer: A (Bilobed and attached at the front (anterior) end of the lower jaw)
The frog’s muscular, sticky, bifid tongue is attached anteriorly inside the margin of the lower jaw and free posteriorly, enabling it to flick rapidly outward to catch insects.
The frog’s muscular, sticky, bifid tongue is attached anteriorly inside the margin of the lower jaw and free posteriorly, enabling it to flick rapidly outward to catch insects.
49. How many pairs of cranial nerves arise from the brain of a frog?
Correct Answer: B (10 pairs)
Amphibians (including frogs) and fishes possess 10 pairs of cranial nerves. Amniotes (reptiles, birds, mammals) possess 12 pairs.
Amphibians (including frogs) and fishes possess 10 pairs of cranial nerves. Amniotes (reptiles, birds, mammals) possess 12 pairs.
50. In female frogs, a mature female can lay approximately how many ova at a time during external fertilization in water?
Correct Answer: C (2500 to 3000)
A mature female frog lays 2,500 to 3,000 ova in water at a time (spawn), where external fertilization occurs followed by indirect development via a swimming tadpole larva.
A mature female frog lays 2,500 to 3,000 ova in water at a time (spawn), where external fertilization occurs followed by indirect development via a swimming tadpole larva.