Home
Current Affairs January 2024

What is the correct answer?

4

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

A. endarch

B. exarch

C. radial

D. closed

Correct Answer :

B. exarch


In roots, the protoxylem lies towards periphery and metaxylem lies towards the centre. Such arrangement of primary xylem is called exarch.

Related Questions

What is the correct answer?

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

What is the correct answer?

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

What is the correct answer?

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

What is the correct answer?

4

Main function of lenticel is

A. transpiration

B. guttation

C. gaseous exchange

D. both (a) & (c)

What is the correct answer?

4

The __________ occurs in layers below the epidermis in dicotyledonous plants.

A. parenchyma

B. sclerenchyma

C. collenchyma

D. aerenchyma

What is the correct answer?

4

A common structural feature of vessel elements and sieve tube elements are

A. pores on lateral walls.

B. presence of p-protein.

C. enucleate condition.

D. thick secondary walls.

What is the correct answer?

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.

What is the correct answer?

4

Lignin is the important constituent in the cell wall of

A. phloem

B. parenchyma

C. xylem

D. cambium

What is the correct answer?

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

What is the correct answer?

4

Which of the following process helps the trichomes in preventing water loss?

A. Where companion cells helps in maintaining the pressure gradient in the sieve tubes.

B. Where plants absorb water through the roots and then give off water vapor through pores in their leaves.

C. Where activity of cork cambium builds pressure on the remaining layers peripheral to phellogen and ultimately these layers dies and slough off.

D. None of the above

What is the correct answer?

4

The given figure shows the T.S of dicot root. Some parts are marked as A, B, C, D, E, & F. Choose the option which shows the correct labelling of marked part.

A. A Epiblema, B Root hair, C Cortex, D Endodermis, E Pith, F Pericycle

B. A Cortex, B Pith, C Epiblema, D Endodermis, E Root hair, F Pericycle

C. A Epiblema, B Endodermis, C Cortex, D Root hair, E Pith, F Pericycle

D. A Cortex, B Epiblema, C Pith, D Endodermis, E Root hair, F Pericycle

What is the correct answer?

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.

What is the correct answer?

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

What is the correct answer?

4

Cork cambium and vascular cambium are

A. the parts of secondary xylem and phloem.

B. the parts of pericycle.

C. lateral meristems.

D. apical meristems.

What is the correct answer?

4

The apical meristem of the root is present

A. in all the roots.

B. only in radicals.

C. only in tap roots.

D. only in adventitious roots.

What is the correct answer?

4

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

A. endarch

B. exarch

C. radial

D. closed

What is the correct answer?

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

What is the correct answer?

4

A tissue is a group of cells which are

A. similar in origin, but dissimilar in form and function.

B. dissimilar in origin, form and function.

C. dissimilar in origin, but similar in form and function.

D. similar in origin, form and function.

What is the correct answer?

4

T.S. of dicot stem is given below, certain parts have been marked by alphabets (A I). Choose the option which shows their correct labelling.

A. A Epidermis, B Epidermal hair, C Parenchyma, D Starch sheath, E Hypodermis (collenchyma), F Vascular bundle, G Bundle cap, H Medulla or pith, I Medullary rays

B. A Epidermal hair, B Epidermis, C Hypodermis (collenchyma), D Parenchyma, E Endoderm is (Starch Sheath), F Pericycle, G Vascular bundle, H Medullary rays, I Medulla or pith

C. A Epidermal hair, B Epidermis, C Hypodermis (collenchyma), D Starch sheath, E Parenchyma, F Vascular bundle, G Bundle cap, H Medulla or pith, I Medullary rays

D. A Epidermal hair, B Epidermis, C Parenchyma, D Hypodermis (collenchyma), E Starch sheath, F Vascular bundle, G Bundle cap, H Medulla or pith, I Medullary rays

What is the correct answer?

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.

What is the correct answer?

4

In land plants, the guard cells differ from other epidermal cells in having

A. cytoskeleton.

B. mitochondria.

C. endoplasmic reticulum.

D. chloroplasts.

What is the correct answer?

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

What is the correct answer?

4

A student was given a tissue to observe under the microscope. He observes the tissue and concludes that the tissue is a type of simple plant tissue and provides mechanical support to young stem and petiole of leaf.
Identify the tissue.

A. Parenchyma

B. Collenchyma

C. Sclerenchyma

D. Xylem parenchyma

What is the correct answer?

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

What is the correct answer?

4

One of the primary function of the ground tissue in a plant is

A. photosynthesis.

B. to protect the plant.

C. to anchor the plant.

D. water and sugar conduction.

What is the correct answer?

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

What is the correct answer?

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

What is the correct answer?

4

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

A. sclerenchyma

B. parenchyma

C. collenchyma

D. aerenchyma

What is the correct answer?

4

Phellogen and phellem respectively denote

A. cork and cork cambium,

B. cork cambium and cork,

C. secondary cortex and cork,

D. cork and secondary cortex,

What is the correct answer?

4

An organised and differentiated cellular structure having cytoplasm but no nucleus is called _________.

A. vessels

B. xylem parenchyma

C. sieve tubes

D. tracheids