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4

Why grafting is successful in dicots ?

A. In dicots vascular bundles are arranged in a ring.

B. Dicots have cambium for secondary growth.

C. In dicots vessels with elements are arranged end to end.

D. Cork cambium is present in dicots

Correct Answer :

B. Dicots have cambium for secondary growth.


In most dicot stems and roots, secondary growth occurs due to addition of secondary tissues (secondary cortex, secondary phloem and secondary xylem) formed by the activity of vascular cambium in the stelar region inside pericycle and cork cambium in the extrastelar regions (region outside pericycle i.e., cortex)

Related Questions

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4

A vascular bundle in which the protoxylem is pointing to the periphery is called __________.

A. endarch

B. exarch

C. radial

D. closed

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4

Match the terms given in column I with their features given in column II and choose the correct option.
Column-IColumn-II
(Terms)(Features)
A. Fibres(i) Cells are living and thin walled with cellulosic cell wall, store food materials in the form of starch or fat
B. Sclereids(ii) Main water conductive cells of the pteridophytes and the gymnosperms
C. Tracheids(iii) Thick walled, elongated and pointed cells, generally occurring in groups
D. Vessels(iv) Long cylindrical tube like structure and cells are devoid of protoplasm. Characteristic feature of angiosperms
E. Xylem parenchyma(v) Reduced form of sclerenchyma cells with highly thickened lignified cellular walls that form small bundles of durable layers of tissue in most plants.

A. A - (i), B - (ii), C - (iii), D - (iv), E - (v)

B. A - (iii), B - (v), C - (ii), D - (iv), E - (i)

C. A - (iii), B - (i), C - (v), D - (ii), E - (iv)

D. A - (v), B - (iv), C - (iii), D - (i), E - (ii)

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4

Identify A, B and C in the given figure of shoot apical meristem

A. A Leaf primordium, B Shoot apical meristem, C Axillary bud

B. A Leaf primordium, B Shoot apical meristem, C Apical bud

C. A Root hair primordium, B Root apical meristem, C Axillary bud

D. A Root hair primordium, B Root apical meristem, C Terminal bud

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4

The given figures are types of elements (A and B) which constitute one type of complex tissue (c) of a plant . Identify A, B and C.

A. A Tracheid, B Vessel, C Xylem

B. A Vessel, B Tracheild, C Phloem

C. A Fibre, B Tracheid, C Bark

D. A Fibre, B Sclereid, C Casparian strips

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4

The trees growing in desert will

A. show alternate rings of xylem and sclerenchyma.

B. have only conjunctive tissue and phloem is formed by the activity of cambium.

C. show distinct annual rings.

D. not show distinct annual rings.

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4

The given figure shows T.S. of monocot stem. Identify the correct labelling of A to F marked in the given figure.

A. A Epidermis, B Hypodermis, C Vascular bundles, D Phloem, E Xylem, F Ground tissue

B. A Cuticle, B Epidermis, C Sclerenchymatous sheath, D Sclerenchymatous hypodermis, E Parenchymatous sheath, F Phloem

C. A Cuticle, B Epidermis, C Sclerenchymatous hypodermis, D Sclerenchymatous sheath, E Parenchymatous sheath, F Phloem

D. A Cuticle, B Epidermis, C Sclerenchymatous hypodermis, D Sclerenchymatous sheath, E Parenchymatous sheath, F Protoxylem

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4

Cambium is considered as a lateral meristem because

A. it gives rise to lateral branches.

B. it causes increase in girth.

C. it increases height and diameter of a plant.

D. it adds bulk to a plant.

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4

Gymnosperms are also called soft wood spermatophytes because they lack

A. cambium

B. phloem fibres

C. thick-walled tracheids

D. xylem fibres

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4

The given figure shows the secondary growth in a dicot stem. Their parts are marked as A, B, C, D, E & F. Choose the correct labelling of the parts marked as A to F.

A. A Phellem, B Phellogen, C Medullary rays, D Secondary xylem, E Secondary phloem, F Cambium ring

B. A Phellem, B Phellogen, C Medullary rays, D Secondary phloem, E Secondary xylem, F Cambium ring

C. A Phellogen, B Phellem, C Medullary rays, D Secondary xylem, E Secondary phloem, F Cambium ring

D. A Phellem, B Phellogen, C Cambium ring, D Secondary xylem, E Secondary phloem, F Medullary rays

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4

When we peel the skin of a potato tuber, we remove

A. periderm

B. epidermis

C. cuticle

D. leaves

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4

Various functions like photosynthesis, storage, excretion performed by _____________.

A. sclerenchyma

B. parenchyma

C. collenchyma

D. aerenchyma

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4

Apical, intercalary and lateral meristems are differentiated on the basis of

A. origin

B. function

C. position

D. development

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4

Bast fibres are made up of _____________cells.

A. sclerenchymatous

B. chlorenchymatous

C. parenchymatous

D. aerenchymatous

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4

As secondary growth proceeds, in a dicot stem, the thickness of

A. sapwood increases.

B. heartwood increase.

C. both sapwood and heartwood increases.

D. both sapwood and heartwood remains the same.

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4

Match column-I with column-II and choose the correct option.
Column -IColumn -II
A. Bulliform cellsI. Initiation of lateral roots
B. PericycleII. Root
C. Endarch xylemIII. Grasses
D. Exarch xylemIV. Dicot leaf
E. Bundle sheath cellsV. Stem

A. A III, B V, C IV, D I, E II

B. A II, B V, C I, D III, E IV

C. A II, B IV, C I, D III, E V

D. A III, B I, C V, D II, E IV

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4

Match column-I with column-II and choose the correct option.
A. Spring wood orI. Lighter in colour early wood
B. Autumn wood orII. High density late wood
..III. Low density
..IV. Darker in colour
..V. Larger number of xylem elements
..VI. Vessels with wider cavity
..VII. Lesser number of xylem elements
..VIII. Vessels with small cavity

Which of the following combination is correct ?

A. A II, IV, VII, VIII; B I, III, V, VI

B. A I, II, VII, VIII; B III, IV, V, VI

C. A I, III, V, VI; B II, IV, VII, VIII

D. A I, III, VII, VIII; B II, IV, V, VI

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4

Which type of plant tissue is being described by the given statements?
  1. It consists of long, narrow cells with thick and lignified cell walls having a few or numerous pits.
  2. They are dead and without protoplasts.
  3. On the basis of variation in form, structure, origin and development, it may be either fibres or sclereids.
  4. It provides mechanical support to organs.

A. Parenchyma

B. Sclerenchyma

C. Collenchyma

D. Chlorenchyma

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4

A plant tissue when stained showed the presence of hemicellulose and pectin in cells wall of its cells. The tissue is called

A. collenchyma

B. sclerenchyma

C. xylem

D. meristem

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4

The length of different internodes in a culm of sugarcane is variable because of

A. size of leaf lamina at the node below each internode

B. intercalary meristem

C. shoot apical meristem

D. position of axillary buds

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4

Cells of permanent tissues are specialized

A. functionally.

B. only structurally.

C. both structurally and functionally.

D. for mitosis.

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4

Which of the following pair of match is not correct?

A. Pith - Large and well developed in monocotyledonous root.

B. Root hairs - Helps in preventing water loss due to transpiration

C. Sieve tube elements - Its functions are controlled by the nucleus of companion cells.

D. Stomatal apparatus - Consists of stomatal aperture, guard cells and surrounding subsidiary cells

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4

Choose the correct labelling of (A J) in the given figure of T.S. of monocot root.

A. A Root hair, B Epiblema, C Cortex, D Endodermis, E Passage cell, F Pericycle, G Pith, H Phloem, I Metaxylem.

B. A Root hair, B Epiblema, C Cortex, D Endodermis, E Passage cell, F Pith, G Pericycle, H Metaxylem, I Phloem.

C. A Root hair, B Epiblema, C Cortex, D Endodermis, E Pericycle, F Phloem, G Protoxylem, I Metaxylem

D. A Root hair, B Cortex, C Epiblema, D Pericycle, E Endodermis, F Pith, G Phloem, H Protoxylem, I Metaxylem

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4

During the formation of leaves and elongation of stem, some cells left behind from the shoot apical meristem, constitute the

A. lateral meristem

B. axillary bud

C. cork cambium

D. fascicular cambium

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4

Identify types of vascular bundles in given figures A, B and C.

A. Radial; Conjoint closed; Conjoint open

B. Conjoint closed; Conjoint open; Radial

C. Conjoint open; Conjoint closed; Radial

D. Bicollateral; Concentric; Radial

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4

Which of the following is responsible for the formation of an embryonic shoot called axillary bud?

A. Lateral meristem

B. Apical meristem

C. Intercalary meristem

D. Both

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4

Cork is formed from

A. phellogen

B. vascular cambium

C. phloem

D. xylem

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4

Which one of the followings option shows the correct labelling of the parts marked as A, B, C and D in the given figure a lenticel?

A. A Epidermis, B Secondary cortex, C Cork cambium, D Cork

B. A Pore, B Cork cambium, C Secondary cortex, D Cork

C. A Pore, B Cork, C Complimentary cells, D Cork cambium

D. A Epidermis, B Complimentary cells, C Cork cambium, D Secondary cortex

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4

Which of the following statement(s) is/are correct ?
  1. Uneven thickening of cell wall is characteristic of sclerenchyma.
  2. Periblem forms cortex of the stem and the root.
  3. Tracheids are the chief water transporting elements in gymnosperms.
  4. Companion cell is devoid of nucleus at maturity.
  5. The commercial cork is obtained from Quercus suber.

A. (i) and (iv) only

B. (ii) and (v) only

C. (iii) and (iv) only

D. (ii), (iii) and (v) only

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4

The vessel elements of angiosperms differ from other elements of xylem in having

A. simple pits on their radial walls.

B. bordered pits on their lateral walls.

C. simple and bordered pits on their end walls.

D. simple perforation on their end walls.

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4

In an experiment, a student cut a transverse section of young stem of a plant which he has taken from his school garden.
After observing it under the microscope how would he ascertain whether it is a monocot stem or a dicot stem?

A. With the help of bulliform cells.

B. With the help of casparian strips.

C. With the help of vascular bundles.

D. With the help of stomatal apparatus.