BIOLOGY TIMES — January 2018

37. Classification of various tissues is based on
    
    (a) Structure (b) Location
    (c) Type of cell (d) Both a& b


38. The parenchymatous cells present in between the
    xylem and phloem are called
    (a) Cambium (b) Conjunctive tissue
    (c) Pith (d) Pericycle


39. Leaf primordium grows into an adult leaf lamina
    by means of
    (a) Marginal meristem
    (b) Lateral meristem
    (c) First apical meristem
    (d) Apical meristem


40. Totipotency is present in
    (a) Meristem (b) Cambium
    (c) Phloem (d) Cork


41. Impervious nature of cork is due to deposition of
    which chemical
    (a) Lignin (b) Suberin
    (c) Pectin (d) Hemicellulose


42. Special feature of dividing cells is
    (a) Large lacuna
    (b) Thick cell walls
    (c) Dense cytoplasm devoid of lacuna
    (d) Large intercellular space


43. Albuminous cells occurs in
    (a) Xylem (b) Phloem
    (c) Cortex (d) Conjunctive
    parenchyma


44. Shifting of vascular cambium to the outside due
    to formation of secondary xylem on inner side is
    called as
    (a) Abscission (b) Dilation
    (c) Deposition (d) Intussusception


45. A leptocentric vascular bundle has
    (a) Phloem flanked by xylem on interior and
    
    exterior sides only
    (b) Xylem flanked by phloem on interior and
    
    exterior sides only
    (c) Xylem surrounded by phloem
    (d) Phloem surrounded by xylem


46. The only plant cell without the nucleus among the
    following are:
    (a) Cambium cells (b) Xylem vessel elements
    (c) Root hairs (d) Companion cells


47. Amphivasal vascular bundles are found in
    (a) Cycas and dryopteris
    (b) Dracaena and yucca
    (c) Helianthus and cucurbita

(d) Maize and wheat

48. ‘Patua’ of Hibiscus sabdariffa is
    (a) Secondary phloem
    (b) Collenchymatous hypodermis
    (c) Epidermis
    (d) Pericycle


49. When phloem is completely surrounded by
    xylem, the vascular bundle is called
    (a) Concentric leptocentric/amphivasal
    (b) Concentric amphicribal
    (c) Conjoint collateral
    (d) Conjoint bicollateral


50. Centripetal xylem is present in
    (a) Dicot root (b) Dicot stem
    (c) Monocot stem (d) Branches of stem

Secondary growth

51. Which of the following do not have stomata
    (a) Xerophytes (b) Mesophytes
    (c) Hydrophytes (d) Submerged
    hydrophytes


52. Which of the following is responsible for the
    growth in circumference or girth of stem and
    roots of plants?
    (a) Xylem (b) Phloem
    (c) Cortex (d) Cambium


53. Growth rings are well marked in trees growing in
    (a) Shimla (b) Bombay
    (c) Madras (d) Calcutta


54. Trees at sea do not have annual rings because
    (a) Soil is sandy
    (b) There is climatic variation
    (c) There is no marked climatic variation
    (d) There is enough moisture in the atmosphere


55. Which will decay faster when exposed freely?
    (a) Softwood
    (b) Heart wood
    (c) Wood with lots of fibers
    
    (d) Sapwood


56. For a successful graft, the adhesion between stock
    and scion is must, which one of the following is
    the earliest event towards a good graft?
    (a) Production of plasmodesmata in the cells at
    interface of stock and scion
    (b) Coordinated differentiation of vascular
    tissue between the stock and scion
    (c) Regeneration of cortex and epidermis over
    the union of stock and scion