Tag: internal structure of root, stem and leaf

Questions Related to internal structure of root, stem and leaf

In a monocot stem, the vascular bundles are?

botany internal structure of root, stem and leaf internal structure of monocot stem internal structure of monocots internal structure of stem(dicot and monocot)

  1. Arranged in a ring

  2. Arranged alternatively

  3. Present inside endodermis

  4. Scattered in ground tissue

Show answer
Correct Option: D
Explanation:
In a monocot stem, a large number of vascular bundles lie scattered throughout the ground tissue and peripheral bundles are generally smaller than the centrally located ones. The vascular bundles are conjoint, collateral but closed.

So, the correct answer is 'Scattered in ground tissue'.

In monocot stem


(a) Vascular bundles are scattered.
(b) Hypodermis is sclerenchymatous.
(c) Endodermis is well developed.
(d) Stele is atactostele.

botany internal structure of root, stem and leaf internal structure of monocot stem internal structure of monocots internal structure of stem(dicot and monocot)

  1. Only (a) and (b), (d) are correct

  2. Only (c) and (d) are correct

  3. Only (b) is incorrect

  4. All (a),(b),(c) and (d) are correct

Show answer
Correct Option: A
Explanation:

Vascular tissue system composed of vascular bundles and they are scattered. So, the steles are called atactostele. Hypodermis is multilayered and sclerenchymatous. Endodermis is not developed.

So, the correct option is 'a, b, d are correct'.

Select the mismatched pair.

botany internal structure of root, stem and leaf internal structure of monocot stem internal structure of monocots internal structure of stem(dicot and monocot)

  1. Collateral and open vascular bundles- Sunflower stem

  2. Bicollateral vascular bundles - Maize stem

  3. Concentric vascular bundles - Ferns

  4. Radial vascular bundle - Maize root

Show answer
Correct Option: B
Explanation:
A. Collateral open vascular bundles- Xylem is present in the inner side and phloem to the outside and cambium ring is present in between them.
Eg- in dicot stems as in sunflower stem.
B. Bicollateral vascular bundles- one patch of xylem and two patches of cambium are present.
Eg- plants belonging to the family Cucurbitaceae, Solanaceae etc
Mazie belongs to the family Gramineae.
C. Concentric vascular bundles- in which either the xylem or phloem surrounds each other.
Eg- ferns.
D. Radial vascular bundle- Xylem and phloem occupy different radii and alternate each other.
Eg- Dicot and monocot roots (as in maize root).
So, the correct answer is 'Bicollateral vascular bundles - Maize stem'.

Plants have evolved various defences to lessen the impact of predation by herbivores. Choose the correct option for the defence measures in the given plants. Where M-Morphological, C-Chemical, A-Anatomical, P-Physiological.

Acacia Cactus Calotropins
$(1)$ P P M
$(2)$ A M C
$(3)$ P C C
$(4)$ M M C
botany internal structure of root, stem and leaf internal structure of monocot stem internal structure of monocots internal structure of stem(dicot and monocot)

  1. A

  2. B

  3. C

  4. D

Show answer
Correct Option: A

Which type of vascular bundle is found in monocot stem?

botany internal structure of root, stem and leaf internal structure of monocot stem internal structure of monocots internal structure of stem(dicot and monocot)

  1. Conjoint, collateral, open, endarch

  2. Radial, open, diarch

  3. Radial, open, mesarch

  4. Conjoint, collateral, closed, endarch

Show answer
Correct Option: A

Read the following features and choose the correct option about anatomy of dicot and monocot stem.
(i) Collenchymatous hypodermis.
(ii) Vascular bundles are scattered.
(iii) Eustele.
(iv) Ground tissue is not differentiated.
(v) Pericycle absent

botany internal structure of root, stem and leaf internal structure of monocot stem internal structure of monocots internal structure of stem(dicot and monocot)

  1. Dicot stem i,ii,iii ; Monocot stem iv,v

  2. Dicot stem i,ii,v ; Monocot stem iii,iv

  3. Dicot stem iii, v; Monocot stem i,ii,iv

  4. Dicot stem i,iii ; Monocot stem ii, iv, v

Show answer
Correct Option: A
Explanation:
Dicot stem has collenchymatous hypodermis, monocots have sclerenchymatous hypodermis.  In each vascular bundle, the xylem and phloem are separated by a substance called vascular cambium. Eustele is similar to the dictyostele except that the bundles lack an endodermis and are collateral. 
Monocots have vascular bundles throughout their ground tissue, their stems do not have a discernible pith; the parenchyma cells in monocot stems are referred to simply as ground tissue. In monocot roots, the pericycle present only produces the lateral roots. 
So the correct option is 'Dicot stem i,ii,iii ; Monocot stem iv,v'.

Conjoint, collateral, closed and endarch vascular bundles scattered in the ground tissue are found in

botany internal structure of root, stem and leaf internal structure of monocot stem internal structure of monocots internal structure of stem(dicot and monocot)

  1. Dicot root

  2. Monocot root

  3. Dicot stem

  4. Monocot stem

Show answer
Correct Option: D
Explanation:

Conjoint, collateral, closed and endarch vascular bundles scattered in the ground tissue are found in monocot stem. In a monocotyledenous stem the vascular bundles are not arranged in a circle but are usually scattered throughout the ground tissue. There is no clearly defined pith as there is in many dicotyledonous species. The vascular bundles of monocotylenous plants do not contain a layer of meristematic tissue.  

Cortex and pith remain indistinguishable in

botany internal structure of root, stem and leaf internal structure of monocot stem internal structure of monocots internal structure of stem(dicot and monocot)

  1. Monocot stem

  2. Monocot root

  3. Periderm

  4. Dicot stem

Show answer
Correct Option: A
Explanation:

Cortex and pith remain indistinguishable in a monocot stem. The epidermis is a layer of cells that cover the plant body, including the stems, leaves, flowers and fruits, that protects the plant from the outside world. In old stems the epidermal layer, cortex and primary phloem become separated from the inner tissues by thicker formations of cork. But in the monocots the cortex and pith are indistinguishable.
Therefore, the correct answer is option A.

Identify the incorrect statement with respect to monocot stem.
(a) Hypodermis is made up of sclerenchyma
(b) Ground tissue is differentiated
(c) Vascular bundles which are situated towards the centre are larger in size and less in number
(d) Each vascular bundle is conjoint, collateral and closed and xylem is endarch.

botany internal structure of root, stem and leaf internal structure of monocot stem internal structure of monocots internal structure of stem(dicot and monocot)

  1. a, b and c

  2. b, c and d

  3. only b

  4. b and c

Show answer
Correct Option: A

Monocot stem are characterized by

botany internal structure of root, stem and leaf internal structure of monocot stem internal structure of monocots internal structure of stem(dicot and monocot)

  1. Conjoint collateral and open vascular bundle

  2. Conjoint collateral and closed vascular bundle

  3. Radial

  4. None of the above

Show answer
Correct Option: B
Explanation:

Anatomy of the monocot stem shows that while the vascular bundles are oval in shape, numerous and scattered, it is by nature, conjoint, collateral, closed and endarch without any lysigenous activity.

Therefore, the correct answer is option B.