Tag: evs

Questions Related to evs

The roots are important parts of the plant because

evs identifying the plants absorption of water from the soil root system the root system

  1. The roots provide anchorage

  2. The roots help in making food

  3. The roots absorb water

  4. Both A and C

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Correct Option: D
Explanation:

Functions of root:-

  • It helps in the absorption of water and mineral.
  • Holds the soil hence provide anchorage.
  • Modify to store food.
  • In hydrophytes helps to take oxygen called pneumatophores.
  • Provide support to the plant body.
So the correct option is "Both A and C".

Reticulate venation is found in the plants with

evs identifying the plants absorption of water from the soil root system the root system

  1. Tap root system

  2. Fibrous root system

  3. Branched root system

  4. Both A and C

Show answer
Correct Option: A
Explanation:
Dicots are the plant with characters like:-
A) Taproot system
B) Reticulate venation
C) Two cotyledons
D) Secondary growth
So, the correct option is 'Tap root system'.

A plant which does not have roots is?

evs identifying the plants absorption of water from the soil root system the root system

  1. Utricularia

  2. Nelumbo

  3. Trapa

  4. Avicennia

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Correct Option: A
Explanation:

Utricularia is an insectivorous plant. It does not have roots because it is specially modified to trap insects for feeding, so its vegetative organs are not seperated into roots stems and leaves.

The correct option is 'Utricularia'

Herbaceous plant that dies back to ground each year but sprouts again from under ground parts is?

evs identifying the plants absorption of water from the soil root system the root system

  1. Perennial

  2. Biennial

  3. Annual

  4. Winter annual

Show answer
Correct Option: A
Explanation:

A. Herbaceous plant in which the underground part of the plant is alive and survive through unfavourable conditions and then sprout above the ground later are perennial. For example, Piper nigrum etc.

B. The herbs that can live for two years are biennial plants. For example, coriander etc
C. The herbs in which both above ground and underground parts die after a year are annual. For example, basil etc
D. Winter annual herbs are plants which germinate in autumn or winter and live through winter like chickweed etc 
So, the correct answer is 'Perennial'.

Lateral roots originate from

evs identifying the plants absorption of water from the soil root system the root system

  1. Cortex

  2. Epidermis

  3. Endodermis

  4. Pericycle

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Correct Option: D
Explanation:

$\to$ Endodermis is followed by one or more layers of pericycle.

$\bullet$ It is believed to represent the outer boundary of the vascular strand.
$\bullet$ The cells of pericycle are their walled an parenchymatous in the young root.
$\bullet$ Pericycle is a very important layer. A part of vascular cambium is formed by pericycle.
$\bullet$ All lateral roots originate from it.
$\bullet$ It is absent in the roots of some aquatic plants and parasites.

Which of the following is true?

evs identifying the plants absorption of water from the soil root system the root system

  1. Stem branches are endegenous

  2. Stem branches develop from pericycle

  3. Root branches are exogenous

  4. Root branches are endogenous

Show answer
Correct Option: D
Explanation:
  • The parts which arise from the cortical region or the cortex are called exogenous in origin.
  • The parts which arise from the pericycle are called endogenous origin.
  • The lateral roots or root branches originate endogenously as they originate from the pericycle.
  • So, the correct answer is 'Root branches are endogenous'

Root cap is formed by

evs identifying the plants absorption of water from the soil root system the root system

  1. Dermatogen

  2. Calyptrogen

  3. Wound cambium

  4. Vascular cambium

Show answer
Correct Option: B
Explanation:

A. Dermatogen is the primary meristem that forms the outer most layer of a plant or a plant part and forms the epidermis.

B. Calyptrogen is a specialized layer of rapidly dividing cells present at the root tips which continuously divide to form the root cap is formed. 
C. Wound cambium is formed within a masses of cells (callus) which grow over the injured surface of a wound to heal and repair that part.
D. Vascular cambium is a lateral meristem which develops within the vascular bundles to produce xylem to the inner side and phloem to the outer side and is also called fascicular cambium.
So, the correct answer is 'Calyptrogen'.

Root apex has a zone of slow dividing cells in the middle of rapidly dividing cells. It is

evs identifying the plants absorption of water from the soil root system the root system

  1. Quiescent centre

  2. Sluggish centre

  3. Dormant centre

  4. Non-meristematic zone

Show answer
Correct Option: A
Explanation:
  • The root-promeristems that contain the initials of epidermis, cortex and stele is known as Quiescent centre.
  • These cells divide less frequently as they are inactive and are present at the pole of cortex and stele.
  • The cells with QC have small dictyosomes, nuclei and nucleoli with little cytoplasm.
  • These cells also have little endoplasmic reticulum, mitochondria and contain low concentrations of RNA, DNA and protein than the other cells of the root apex.
  • So, the correct answer is 'Quiescent centre'

Tunica corpus theory was proposed by ________

evs identifying the plants absorption of water from the soil root system the root system

  1. Schmidt

  2. Nageli

  3. Hanstein

  4. Hofmeister

Show answer
Correct Option: A
Explanation:

The tunica and corpus theory was given by Schmidt in the year 1924. This theory is applicable only for the shoot apex and not to root. This theory divides the region into two tissue zones which are tunica and corpus.

 The correct answer is A.

A plant with epidermis specialised to absorb mositure from air is?

evs identifying the plants absorption of water from the soil root system the root system

  1. Avicennia

  2. Vanda

  3. Rhizophora

  4. Jussiaea

Show answer
Correct Option: B
Explanation:

A plant with epidermis specialized to absorb moisture from the air is Vanda because vanda is an epiphyte with modified epidermis called velamen. As it stays on the host plant branches, its roots hang in the air absorbing moisture from the atmosphere.

So, the correct option is 'Vanda'.