Internal structure of monocot stem - class-X
Description: internal structure of monocot stem | |
Number of Questions: 62 | |
Created by: Akash Patil | |
Tags: tissue and tissue system plant anatomy and plant physiology botany histology and anatomy of flowering plants internal structure of root, stem and leaf anatomy of flowering plants biology plant tissues and anatomy |
Y- shaped arrangement of xylem vessles is found in
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monocot stem
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dicotstem
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monocot root
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dicot root
Xylem comprises of vessels, tracheids, xylem parenchyma, and restricted xylem strands. the vessel is Y-molded with bigger two round set metaxylem vessels shaping the arms and littler yearly or winding protoxylem vessels, framing the base.
The number of growth rings (sum of the rings of spring wood and autumn wood) in the year 2000 is found to be 20. What will be the number of annual rings in 2018?
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38
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8
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28
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18
Every year one spring ring and one autumn rings make one annual ring which is used to estimate the age of the plant.
Read the following statements and select the correct option.
A. Damage to chordae tending of semilunar valves in aorta causes back flow of blood in left ventricle.
B. Closure of atrio-ventricular valves during ventricular systole generates first heart sound
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Both statements are correct
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Only statement B is correct
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Only statement A is correct
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Both statements are incorrect.
The semilunar valves are present inbetween the aorta and the left ventricle (aortic semilunar valve) and between the right ventricle and the pulmonary artery (pulmonary semilunar valve). The aortic semilunar valve functions to pevent backflow of blood into the ventricle. Damage to chordae tendinae of the aortic semilunar valve will therefore cause backflow of blood to the left ventricle. The first heart sound is produced by the closure of the mitral and the tricuspid valve, that are the atrioventricular valves.
In a monocot stem, the vascular bundles are?
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Arranged in a ring
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Arranged alternatively
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Present inside endodermis
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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.
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Only (a) and (b), (d) are correct
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Only (c) and (d) are correct
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Only (b) is incorrect
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All (a),(b),(c) and (d) are correct
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.
Select the mismatched pair.
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Collateral and open vascular bundles- Sunflower stem
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Bicollateral vascular bundles - Maize stem
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Concentric vascular bundles - Ferns
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Radial vascular bundle - Maize root
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 |
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A
-
B
-
C
-
D
Which type of vascular bundle is found in monocot stem?
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Conjoint, collateral, open, endarch
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Radial, open, diarch
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Radial, open, mesarch
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Conjoint, collateral, closed, endarch
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
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Dicot stem i,ii,iii ; Monocot stem iv,v
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Dicot stem i,ii,v ; Monocot stem iii,iv
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Dicot stem iii, v; Monocot stem i,ii,iv
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Dicot stem i,iii ; Monocot stem ii, iv, v
Conjoint, collateral, closed and endarch vascular bundles scattered in the ground tissue are found in
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Dicot root
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Monocot root
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Dicot stem
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Monocot stem
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
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Monocot stem
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Monocot root
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Periderm
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Dicot stem
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.
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a, b and c
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b, c and d
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only b
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b and c
Monocot stem are characterized by
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Conjoint collateral and open vascular bundle
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Conjoint collateral and closed vascular bundle
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Radial
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None of the above
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.
What is present around a vascular bundle of a monocot stem?
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Pericycle
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Endodermis
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Pericycle & endodermis both
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Bundle sheath
Lysigenous cavity and Y-shaped xylem occurs in
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Dicot stem
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Monocot root
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Monocot stem
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Dicot root
Lysigenous intercellular spaces is type of intercellular space arises through dissolution of entire cells, which are therefore called as lysigenous cavity. These cavities of intercellular spaces store up water, gases and essential oils in them. The examples are commonly found in water plants and many monocotyledonous stems. The secretory cavities in Eucalyptus, Citrus and Gossypium are good examples. In monocot stem the vascular bundle encloses both xylem and phloem. Xylem is found towards the inner surface and phloem towards the outer surface. Cambium is absent. Hence, the vascular bundles are described as conjoint, collateral and closed. In the xylem, there are two metaxylem and two protoxylem vessels arranged in the shape of Y.
Which type of vascular bundles are found in monocot stem?
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Collateral, open, endarch
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Radial, open, diarch
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Radial, open, mesarch
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Collateral, closed, endarch
Monocot stem vascular bundles are found irregularly scattered in the ground tissue. Towards the periphery, the bundles are smaller in size while towards the centre, they are larger in size. The smaller bundles are younger, while the larger ones are older. Hence, the arrangement is described as centrifugal.
Hard bast (bundle cap) occurs in
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Sunflower stem
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Wheat stem
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Sunflower root
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Both of (A) and (C)
Hard bast is the patch of sclerenchyma present on outside of each vascular bundle, thereby forming a bundle cap over each bundle. They serve to provide additional mechanical support to the stem and are present in Sunflower stem. Wheat stem represent a monocot stem in which each vascular bundle is surrounded by thick walled bundle sheath, they do not have hard bust. Root is marked by presence of primary xylem and phloem in different radii, separated from each other.
Therefore, the correct answer is option A.
Which type of vascular bundles are found in monocot stem?
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Collateral, open, endarch
-
Radial, open, diarch
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Radial, open, mesarch
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Collateral, closed, endarch
Monocot stem vascular bundles are found irregularly scattered in the ground tissue. Towards the periphery, the bundles are smaller in size while towards the centre, they are larger in size. The smaller bundles are younger, while the larger ones are older. Hence, the arrangement is described as centrifugal or endarch.
In monocot stems, secondary growth cannot occur, because vascular bundles are
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Scattered
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Open
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Closed
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Radial
Secondary growth refers to the growth that results from cell division in the cambia or lateral meristems and that causes the stems and roots to thicken, while primary growth is growth that occurs as a result of cell division at the tips of stems and roots, causing them to elongate and gives rise to primary tissue.
What is the characteristics of a vascular bundle of monocot stem?
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Open and surrounded by a sclerenchymatous bundle sheath
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Closed and not surrounded by bundle sheath
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Closed and surrounded by bundle sheath
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Open and not surrounded by a bundle sheath
In a monocot 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 character of monocot is
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Net-veined leaves
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Annual rings
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Seed with two masses of stored food
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Conducting strands scattered in ground tissue
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.
An example of monocots showing secondary growth in stem is
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Lilium
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Cocos
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Asparagus
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Yucca
Secondary growth is increase in the circumference / girth of the plant organs due to the formation of secondary tissues in stelar and extra stelar regions. Normally secondary growth takes place in roots and stem of dicotyledons and gymnosperms. Due to lack of cambium in monocotyledons, secondary growth is absent. But exceptionally, secondary growth takes place in some monocotyledons, such as palm, Yucca, Dracaena etc.
Conjoint, collateral and closed vascular bundles are found in
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Monocot stem
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Monocot root
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Dicot stem
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Dicot root
In monocot stem vascular bundles are found irregularly scattered in the ground tissue. Towards the periphery, the bundles are smaller in size, while towards the centre, they are larger in size. The smaller bundles are younger, while the larger ones are older. Hence, the arrangement is described as centrifugal.
Cambium found in vascular bundles of dicot stem is _______________.
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Intercalary meristem
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Fascicular cambium
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secondary meristem
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All of the above
Atactostele is found in
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Dicot stem
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Monocot stem
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Dicot root
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Monocot root
Atactostele is a type of eustele, found in monocots, in which the vascular tissue in the stem exists as scattered bundles. Most seed plant stems possess a vascular arrangement, which has been interpreted as a derived siphonostele and is called as eustele. There is also a variant on the eustele found in monocots, like maize and rye. The variation has numerous scattered bundles in the stem and is called as an atactostele.
The stele present in Equisetum is
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Haplostele
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Actinostlele
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Plectostele
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Siphonostele
- Haplostele consist of smooth ore of xylem which is surrounded by a phloem ring.ex-Seleginella
- Actinostele consist of star shape xylem core with many radiating arms.ex-Lycopodium
- Plectostele consist of xylem core broken into a number of parallel plates.ex-Lycopodium clavatum
- Siphonostele is a protostele with central pith and considered to be the most advance stele.ex-Equisetum.
Which of the following tissue is absent in vascular bundles of monocot stem?
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Xylem
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Phloem
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Cambium
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All of the above
Which of the following would you consider to prove that a plant is a monocot?
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Leaves with reticulate venation
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Taproot system
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Vascular bundles are closed
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Presence of cambium
In the monocots, the vascular bundles are of the collateral and closed type. The closed vascular bundles lack the cambium and cannot show secondary growth. In the stem, vascular bundles are found scattered in the ground tissue. They are more in number at the periphery as compared to the centre. In the monocot roots, the vascular bundles are closed type an found in the stele.
Conjoint and closed vascular bundles with no phloem parenchyma may be observed in
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Monocot stem
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Monocot root
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Dicot stem
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Dicot root
In monocot stem, all the vascular bundles, the xylem and phloem are in the same line; cambium is absent; phloem is external to xylem; protoxylem faces the centre. Hence, the vascular bundles are described as conjoint, collateral, endarch and closed.
Hypodermis in monocotyledonous stem is?
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Parenchymatous
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Chlorenchymatous
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Collenchymatous
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Sclerenchymatous
The region present below the epidermis in monocot stem is hypodermis. It is composed with sclerenchyma. Sclerenchyma is dead mechanical tissue. It provides mechanical strength to the stem.
So, the correct option is 'Sclerenchyma’.
In monocot stem, which among the following is absent?
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Endodermis
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Hypodermis
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Cortex
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Both A and B
In monocot stem, the endodermis is absent. It has a single layer epidermis. The vascular bundles are scattered.
T.S. of stem of Cucurbita can be identified from the T.S. of sunflower stem by the presence of
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Bicollateral vascular bundles
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Conjoint vascular bundles
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Scattered vascular bundles
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Cambium in the vascular bundles
The vascular bundles of cucurbita are many, conjoint, bicollateral, regularly arranged forming a broken ring or scattered in ground tissue and are endarch.
Undifferentiated ground tissue is present in stem of
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Sunflower
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Pisum
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Maize
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Cucurbita
A.Sunflower – Ground tissue is differentiated into hypodermis, general cortex and endodermis, pericycle, medulla and medullary rays.
B.Pisum - Ground tissue is differentiated into hypodermis, general cortex and endodermis, pericycle, medulla and medullary rays.
C.Maize – Ground tissue is undifferentiated.
D.Cucurbita - Ground tissue is differentiated into hypodermis, general cortex and endodermis, pericycle, medulla and medullary rays.
So, the correct option is ‘Maize’.
Secondary growth does not occur in monocots as their vascular bundles are
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Radial
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Scattered
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Enclosed by sclerenchyma
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Closed
Secondary growth does not take place in monocotyledons, because of the absence of cambium between xylem and phloem in vascular bundles. These vascular bundles are called closed vascular bundles.
So, the correct option is ‘Closed’.
Grafting is not possible in monocots because they
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Lack cambium
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Have scattered vascular bundles
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Have parallel venation
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Are herbaceous
In monocot stem, cambium is absent in the vascular bundles. Due to this, grafting is not possible in monocot stem
So, the correct answer is ‘Lack cambium’
Conjoint and closed vascular bundles with no phloem parenchyma are observed in
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Monocot stem
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Dicot stem
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Monocot root
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Dicot root
A.Monocot stem - conjoint, closed vascular bundles are present, in which phloem parenchyma is absent in the phloem.
Which of the following characters is not found in the transverse section of monocot stem?
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Sclerenchymatous bundle sheath
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Lysigenous cavity
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Sclerenchymatous hypodermis
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Starch sheath
The anatomy of monocot stem shows outer single layered epidermis with cuticle and stomata, sclerenchymatous hypodermis, large, wide parenchymatous ground tissue. In this vascular bundles are scatteredly arranged. So the stele is called Atactostele. Vascular bundles are outerly surrounded by sclerenchymatous fibres. So they are called fibrovascular bundles and are collateral, conjoint, closed with endarch xylem. Protoxylem lacuna is present. General cortex, endodermis, pericycle, medulla and medullary rays are absent.
So, the correct option is ‘Starch sheath’.
Water containing Lysigenous cavity is present within the vascular bundles.
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Monocot stem
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Dicot stem
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Monocot root
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Dicot root
The stele found in monocot is:
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Haplostele
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Atactostele
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Dictyostele
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Actinostele
The stele is the central part of the root and stem which contains tissues derived from the procambium, in monocots, the vascular bundles are scattered and the stele is an atactostele.
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Monocot stem
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Dicot stem
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Monocot root
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Dicot root
The Y-shaped arrangement of xylem vessels is found in monocot stem, two metaxylem vessels are located at the upper two arms, while the base or the stick of the letter consists of one or two protoxylem vessels.
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protoxylem
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metaxylem
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phloem
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ground tissue
In monocot stem (Maize), the xylem appears Y shaped. The lowermost or innermost protoxylem undergoes disintegration to produce lysigenous cavities also called the protoxylem lacuna.
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Phloem parenchyma is absent.
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Vascular bundles are scattered, conjoint, collateral and closed
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Each vascular bundle is surrounded by a bundle sheath.
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Ground tissue is differentiated into cortex, endodermis, pericycle and pith
In a monocot stem (Example Maize), the stem is differentiated into Epidermis, hypodermis and ground tissue. In the ground tissue are embedded vascular bundles that are conjoint, colateral and closed.The vascular bundles are not enclosed by endodermis and pericycle.
Schlerenchymatous hypodermis is found in?
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Dicot root
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Monocot leaf
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Dicot stem
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Monocot stem
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Stems and roots of dicots
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Stems and roots of gymnosperms
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Stems and roots of monocots
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Both (b) and (c)
Stems of monocots do not have lateral or secondary cambium. Roots of both monocots and dicots do not have secondary or lateral cambium. Hence, true secondary growth does not occur in stems and roots of monocots. But, in some exceptional cases if secondary growth takes place due to dedifferentiation of tissue cells of the cortex, pericycle etc into meristematic tissue this type of secondary growth is called anomalous secondary growth.
The lacunae in the vascular bundles of monocot stem is
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A mucilage canal
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Protoxylem lacuna
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Lysigenous cavity
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Both B and C
The first xylem formed is called as protoxylem. Protoxylem is later torn apart and a cavity is formed. The entire protoxylem is dissolved hence, such cavity is called as lysigenous cavity. The protoxylem shows an empty space, called as 'lacuna'.
Transverse section of a material exhibits conjoint collateral endarch and closed bundles scattered in a ground tissue, what should be the material?
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Monocot root
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Dicot root
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Monocot stem
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Dicot stem
Monocot stem vascular bundles are found irregularly scattered in the ground tissue.
T.S. of a material exhibits conjoint collateral endarch and closed bundles scattered in a ground tissue. What should be the material?
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Monocot root
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Dicot root
-
Monocot stem
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Dicot stem
Monocot stem vascular bundles are found irregularly scattered in the ground tissue. Towards the periphery, the bundles are smaller in size while towards the centre, they are larger in size. The smaller bundles are younger, while the larger ones are older. Hence, the arrangement is described as endarch.
Atactostele is found in
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Dicot stem
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Monocot stem
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Dicot root
-
Monocot root
Monocot stems, in which the stele consists of many vascular bundles in a complex arrangement, are said to have an atactostele.
Stem of date palm increases in girth due to activity of:
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Intercalary meristem
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Apical meristem
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Lateral meristem
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None of the above
Date palm is a monocot and lack lateral meristem; the meristem present along the sides causing the increase in girth of the plant.
Lysigenous cavity and 'Y'-shaped xylem occurs in
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Dicot stem
-
Monocot root
-
Monocot stem
-
Dicot root
Lysigenous intercellular spaces is type of intercellular space arises through dissolution of entire cells, which are therefore called as lysigenous cavity. These cavities of intercellular spaces store up water, gases and essential oils in them. The examples are commonly found in water plants and many monocotyledonous stems. The secretory cavities in Eucalyptus, Citrus and Gossypium are good examples. In monocot stem the vascular bundle encloses both xylem and phloem. Xylem is found towards the inner surface and phloem towards the outer surface. Cambium is absent. Hence, the vascular bundles are described as conjoint, collateral and closed. In the xylem, there are two metaxylem and two protoxylem vessels arranged in the shape of Y.
Endodermis is not differentiated in which of the following
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Monocot root
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Dicot root
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Monocot stem
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Dicot stem
In monocot stem, cortex is not differentiated into hypodermis, general cortex and endodermis. In the place of cortex a large, wide region is present called Ground tissue is present. It is parenchymatous, stores water and food materials. In this vascular bundles are present scatteredly.
So, the correct option is ‘monocot stem’
Fibrovascular bundles or vascular bundles covered by sclerenchymatous sheath are found in
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Monocot leaf
-
Monoct stem
-
Monocot root
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Dicot stem
A.Monocot leaf – vascular bundles are covered by parenchymatous bundle sheath.
B. Monocot stem – vascular bundles are covered by sclerenchymatous fibres. So these are called fibrovascular bundles.
C. Monocot root – there is no any covering around the vascular bundles.
D. Dicot stem – there is no any covering around the vascular bundles.
So, the correct option is ‘Monocot stem’.
Phloem parenchyma is absent in
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Dicot root
-
Dicot leaf
-
Monocot stem
-
Dicot stem
A.Dicot root – phloem parenchyma is present.
B.Dicot leaf – Phloem parenchyma is present.
C.Monocot stem – phloem parenchyma is absent.
D.Dicot stem – Phloem parenchyma is present.
So, the correct answer is 'Monocot stem'.
In monocot stem, the pericycle is?
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Indistinguishable
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One layered
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Two layered
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Multi layered
A T.S. shows conjoint, collateral, endarch and closed bundles scattered in a ground tissue. It is?
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Dicot stem
-
Monocot stem
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Dicot root
-
Monocot root
A.Dicot stem – collateral, conjoint, endarch, open vascular bundles present in the form of rings.
B.Monocot stem – collateral, cojoint, endarch, closed vascular bundles present in the form of scattered manner in a ground tissue.
C.Dicot root – radial vascular bundles are present.
D.Monocot root – radial vascular bundles are present.
So, the correct option is ‘Monocot stem’.
Which of these characters does$/$ do not apply to vascular bundle of monocot stem?
I. Conjoint
II. Endarch protoxylem
III. Open
IV. Phloem parenchyma is absent.
-
I and II only
-
II and III
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III and IV
-
III
-
I and IV only
I.Conjoint – applicable – because xylem and phloem are present side by side in the vascular bundles.
II.Endarch protoxylem – applicable – because protoxylem is present towards medulla side and metaxylem is present towards the pericycle side.
III.Open – not applicable – because, cambium is absent between the xylem and phloem in the vascular bundles.
IV.Phloem parenchyma is absent – applicable – in the phloem of monocots phloem parenchyma is not present.
So, the correct option is ‘III’
Monocot stem has
-
Bicollateral closed vascular bundles
-
Bicollateral open vascular bundles
-
Collateral open vascular bundles
-
Collateral closed vascular bundles
A.Bicollateral closed vascular bundles – Not present in any plants
B.Bicollateral open vascular bundles – found in the stems of Cucurbitaceae members
C.Collateral open vascular bundles – found in the dicotyledonous stems.
D.Collateral closed vascular bundles – found in the monocotyledonous stems.
So, the correct option is ‘Collateral closed vascular bundles’.
A structure absent in monocot is
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Sieve tubes
-
Stomata
-
Cambium
-
Vessels
In monocot stem, epidermis, hypodermis, ground tissue, and vascular bundles are present. General cortex, endodermis, pericycle, medulla, medullary are absent. In the phloem, phloem parenchyma is also absent. Xylem and phloem are present on same radii, and also present side by side. So they are also called Collateral and Conjoint vascular bundles. In the vascular bundles, cambium is absent between xylem and phloem, So these are closed vascular bundles. In the xylem, protoxylem is towards the centre, and metaxylem is towards the periphery. So, it is an endarch xylem.
Which one is false about monocot stem?
I. Vascular bundles is scattered, cojoint, close, surrounded by sclerenchymatous bundle sheath and cavity.
II. Hypodermis is scelerenchymatous.
III. Peripheral vascular bundles is smaller than centrally placed ones.
IV. Ground tissue is differentiated into cortex, pericycle, pith, etc.
V. Homogeneous parenchymatous ground.
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I, III, IV
-
III, IV
-
IV
-
V
The monocot stem shows the following characteristics:
Vascular bundles are scattered in
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Bryophytes
-
Dicot root
-
Dicot stem
-
Monocot stem
In monocot stems, the vascular bundles are dispersed. In dicot stems, the vascular bundles are arranged in ring.
Monocot characteristics are
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Fibrous root system, parallel-veined leaves, trimerous flowers and two cotyledons
-
Fibrous root system, parallel-veined leaves, trimerous flowers and one cotyledon
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Fibrous root system, reticulate veined leaves, trimerous flowers and one cotyledon
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Tap root system, parallel venation, trimerous flowers and one cotyledon
Monocot plants, as the name suggests have only one cotyledon. these plants have characteristic features like fibrous root system because the radicle is short-lived, thus replaced by adventitious roots. They also have parallel-veined leaves and trimerous flowers.
Oil cavities of Citrus are
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Lysigenous
-
Schizogeneous
-
Schizolysigneous
-
Intercellular spaces.
Lysigenous intercellular spaces: These cavities of intercellular spaces store up water, gases and essential oils in them. The examples are commonly found in water plants and many monocotyledonous plants. The secretory cavities in Eucalyptus, Citrus and Gossypium are good examples.