Multiple Choice Questions

Advertisement

Casparian strips are present in :

  • cortex

  • epidermis

  • endodermis


C.

endodermis

The casparian strips are thick depositions of lignin or suberin on the walls of eridodermis. These are impervious to water and has discovered by Caspari.


Advertisement

Assertion: In angiosperms, transport of food and water is more efficient than gymnosperms and pteridophytes.

Reason: In angiosperms longitudinally arranged sieve elements and vessels with perforated end walls are present.

  • If both assertion and reason are true and reason is the correct explanation of assertion

  • If both assertion and reason are true but reason is not the correct explanation of assertion

  • If assertion is true but reason is false

  • If both assertion and reason are false.


Assertion : In woody stems, the amount of heart wood continues to increase year after year.

Reason : The cambial activity continues uninterrupted.

  • If both assertion and reason are true and reason is the correct explanation of assertion

  • If both assertion and reason are true but reason is not the correct explanation of assertion

  • If assertion is true but reason is false

  • If both assertion and reason are false


Assertion : Petroplants produce large amount of latex.

Reason : The latex contains long chain hydrocarbons.

  • If both assertion and reason are true and reason is the correct explanation of assertion

  • If both assertion and reason are true but reason is not the correct explanation of assertion

  • If assertion is true but reason is false

  • If both assertion and reason are false


Which one of the following statements pertaining to plant structure is correct?

  • Cork lacks stomata, but lenticels carry out transpiration.

  • Passage cells help in transfer of food from cortex to phloem

  • Sieve tube elements possess cytoplasm but no nuclei.

  • The shoot apical meristem has a quiescent centre


Advertisement

Plasmodesmata connections help in

  • cytoplasmic streaming

  • synchronous mitotic divisions

  • locomotion of unicellular organism

  • movement of substances between cells


The quiescent centre in root meristem serves as a

  • site for storage of food which is utilized during maturation

  • reservoir of growth hormones

  • reserve for replenishment of damaged cells of the meristem

  • region for absorption of water


Assertion : Water and mineral uptake by root hairs from the soil occurs through apoplast until it reaches endodermis.

Reason : Casparian strips in endodermis are suberized

  • If both Assertion and Reason are true and the reason is the correct explanation of the assertion

  • If both Assertion and Reason are true but the reason is not the correct explanation of the assertion

  • If Assertion is true statement but Reason is false

  • If both Assertion and Reason are false statements


In a dicotyledonous stem, the sequence of tissues from the outside to the inside is

  • phellem - pericycle - endodermis - phloem

  • phellem - phloem - endodermis - pericycle

  • phellem - endodermis - pericycle - phloem

  • pericycle - phellem - endodermis - phloem


Advertisement
<

When does a plant wilt?

  • When phloem is blocked

  • When xylem is blocked

  • Pith is removed

  • A few leaves are removed


Advertisement