NEET BIOLOGY
Unit 19 ANATOMY OF FLOWERING PLANTS
PRIMARY STRUCTURE OF PLANTS
PLANT ANATOMY
It is the branch of Botany which deals with study of internal structures and organization of plants by the section cutting is called Plant anatomy.
Anatomy is a Greek Word. Ana asunder & temnein to cut. Plant anatomy is also called as Internal Morphology.
N.Grew is known as father of plant anatomy.
K.A. Chaudhary is known as father of Indian plant Anatomy.
PLANT TISSUE
An organized group of cells which is having similar or dissimilar in shape, having a common origin and usually performing a common function is called tissue.
The term tissue was coined by Nehemiah Grew.
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PLANT ANATOMY
MERISTEMATIC TISSUE :
Term given by Nageli.
Meristem : A meristem is a localized region in which actual cell division occurs.Growth in plants is largely restricted to specialised regions of active cell division called meristerm.
CHARACTERSTIC OF MERISTEMATIC TISSUE :
It is an undifferentiated tissue.
They have prominent and large nucleus.
They do not have intercellular spaces. Cells are closely fitted (Packed) together. So it is a compact
tissue.
Meristematic cells have only primary cell wall which is thin and flexible (elastic) and made up of cellulose.Secondary cell wall is absent.
They have dense cytoplasm.
Cell cycle of meristem is in continuous state of division. It means they have the capacity to divide. So meristematic tissue is composed of immature cells.
Cells of meristem are small and isodiametric.
Normally vacuoles are absent in meristematic cells but if present they are small.
Meristematic cells are metabolically highly active so lack of reserve food occur in these cells.
Plastids are absent in meristems. If they are present, then only in the proplastid stage ER is poorly
developed.
CLASSIFICATION OF MERISTEMATIC TISSUE :
MERISTEMATIC TISSUE BASED ON ORIGIN AND DEVELOPMENT
On the basis of origin and development meristems can be divided into following three types :
(i) Promeristem/Embryonic Meristem/Primordial Meristem :
This meristem develops in begining during embryonic stage.
They divide and give rise to primary meristem.
(ii) Primary meristem :
Meristematic cell developed from promeristem are known as primary meristem.
These cells are always in division phase and form primary permanent tissue.
They are present below the promeristem at shoot and root apices, at the apex of leaves and in
intercalary parts.
(iii) Secondary meristem :
These are the meristems developed from primary permanent tissues. They are not present in the embryonic
stage of the plant. These are present in mature region of root and stem of many plants particularly those
that produce woody axis.
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PLANT ANATOMY
Axillary bud is derived from shoot apical meristem .
Both apical meristem and intercalary meristem are primary meristem, because they appear early in life of a plant and contribute to the formation of the primary plant body.
Lateral meristems are cylindrical.
Intrafascicular cambium is an example of primary lateral meristem .
Interfascicular cambium and cork cambium (phellogen) are examples of secondary lateral meristem .
In the dicot stem, vascular cambium is partly primary and partly secondary in origin .
In the dicot root, vascular cambium is completely secondary in origin . “Parenchymatous cells are generally isodiametric .
Collenchymatous cells are much thickened at the corners, due to deposition of pectin, cellulose and
hemicellulose. Collechyma is present below epidermis either as a homogenous layer or in patches in
herbaceous dicotyledonae stem.
Cell walls of sclerenchymatous cells are thick and lignified .
Sclereids are commonly found in the fruit wall of nuts, pulp of fruits like guava, pear & sapota, seed coats of legumes and leaves of tea.
Tracheids are unicellular, whereas vessels are multicellular .
Vessel is a long cylindrical tube-like structure made up of many cells called vessel elements .
Xylem fibres have highly thickened walls and obliterated central lumens .
The radial conduction of water takes place by the ray parenchymatous cells .
In stems, the primary xylem is endarch, whereas in roots, the primary xylem is exarch .
Gymnosperms have albuminous cells and sieve cells. They lack sieve tube and companion cells .
The companion cells are specialised parenchymatous cells, which are closely associated with sieve tube elements The companion cells help in maintaining the pressure gradient in the sieve tubes .
Phloem parenchyma is absent in most of the monocolyledonae .
Phloem fibres (Bast fibres) are generally absent in primary phloem .
Enucleate condition is found in mature sieve tube element and in mature vessel element.
Protophloem has narrow sieve tubes, whereas metaphloem has bigger sieve tubes .
Jute, flax and hemp fibres are used commercially .
Tissue systems are of three types on the basis of their structure, location and function .
Epidermal cells are parenchymatous .
Cuticle is absent in roots .
The stomatal aperture, guard cells and surrounding subsidiary cells are together called stomatal apparatus. . The root hairs are unicellular elongations of epidermal cells .
The trichomes in the shoot system are usually multicellular .
The ground tissue system consists of parenchyma, collenchyma and sclerenchyma .
Radial vascular bundles are found in roots.
Endodermal cells of roots are barrel-shaped having Casparian strips on radial and tangential walls. These are of a waxy-material-suberin.
In dicot root, pith is small or inconspicous, whereas in monocots roots pith is large and well develope
In roots conjunctive tissue is present between the xylem and the phloem. It is made up of parenchyma
Dicot roots are usually diarch to Tetrach (Rerely hexarch), whereas monocot roots are usually polyarc
IIT-JEE | PRE-MEDICAL | CBSE | FOUNDATION
PLANT ANATOMY
Ex.1 A group of cell alike in form, function and origin is
called
(A) Organ (B) Organella
(C) Tissue (D) None of these
Sol. (C)
Ex.2 Companion cells are closely associated with
Or
Transport of food material in higher plants takes
place through
(A) Sieve elements (B) Vessel elements
(C) Trichomes (D) Guard cells
Sol. (A) : Companion cells are connected with sieve
elements by complex plasmadesmata
Ex.3 See the following figures and identify the types of
simple tissue marked by alphabets
(A) A - Sieve tube, B - Companion cell, C - Phloem
fibre
(B) A - Sieve tube, B - Phloem parenchyma, C -
Phloem fibre
(C) A - Vessel, B - Xylem parenchyma, C -
Companion cell
(D) A - Sieve tube, B - Phloem parenchyma, C -
Companion cell
Sol. (D)
Ex.4 Interfascicular cambium develops from the cells of
(A) Pericycle (B) Medullary rays
(C) Xylem parenchyma (D) Endodermis
Sol. (B)
Ex.5 The only plant cells without nuclei among the
following are
Or
The tissue which is living but does not possess
nucleus in mature state is
(A) Cambium cells (B) Cells of pericycle
(C) Xylem parenchyma (D) Sieve tube
Sol. (D) : In sieve tubes, nucleus is present only in young
stage and without nuclei at maturity
Ex.6 Sieve tubes are better suited for translocation,
because
(A) Possess broader lumen and perforated cross
walls
(B) Are broader than long
(C) Possess bordered pits
(D) Possess no end walls
Sol. (A)
Ex.7 The root apex is subterminal beacuse it
(A) Is covered by tunica cells
(B) Is covered by root hairs
(C) Has many corpus cells
(D) Is covered by root cap
Sol. (D) A group of initial cells, present at the subterminal
region of the growing root tip, which is protected
by a root cap is called root apical meristem or root
apex.
Ex.8 P – protein is found in
(A) Collenchyma (B) Parenchyma
(C) Xylem (D) Sieve tube
Sol. (D) : A sieve tube is analogous to RBC, both being
living but enucleated at maturity. A network of fibres
of P1 and P2 protein is present in the central part of
lumen of sieve tube which controls movement of
materials and with callose, the sealing of pores after
injury.
Ex.9 Function of companion cells is
(A) Loading of sucrose into sieve elements by
passive transport
(B) Loading of sucrose into sieve elements
(C) Providing energy to sieve elements for active
transport
(D) Providing water to phloem
Sol. (B)
Ex.10 Casparian strips are present in the __________ of
the root
(A) Epiblema (B) Cortex
(C) Pericycle (D) Endodermis
SOLVED EXAMPLE
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1. Bamboo, grass and mint stem elongate by the
activity of -
(A) Primary meristem (B) Secondary meristem
(C) Intercalary meristems (D) Apical meristems
2. Maximum growth in root occurs –
(A) At its tip (B) Towards light
(C) Behind the apex (D) Towards apex
3. Periclinal division in a cell takes place by -
(A) Vertical cleavage
(B) Transverse cleavage
(C) Perpendicular cleavage
(D) Tangential cleavage
4. Monocot leaves grow by -
(A) Apical meristem (B) Lateral meristem
(C) Intercalary meristem (D) Dermatogen
5. Which of the following is a primary meristem -
(A) Intra fascicular cambium
(B) Cork cambium
(C) Vascular cambium in roots
(D) None of the above
6. In plants, during embryonic condition –
(A) All cells of the embryo divide
(B) Meristematic activity is confined to single apical
cell
(C) Meristematic activity is confined to a group of
apical cells
(D) Apical & lateral cells only divide
7. Which of the following plants grow by a single
“apical cell” -
(A) Monocots (B) Dicots
(C) Gymnosperms (D) Bryophyta
8. Which of the following is secondary meristem
(A) Protoderm (B) Procambium
(C) Cork cambium (D) All of the above
9. The function of root cap is -
(A) Protection of root tip and control of geotropic
movement
(B) Storage of food products
(C) Absorption of nutrients
(D) None of the above
10. Tunica is a rib meristem because it divides in -
(A) Anticlinal plane only
(B) Periclinal plane only
(C) Both 1 & 2
(D) Several different planes
11. The cells of a permanent tissue do not divide
because these are -
(A) Dead (B) Enucleate
(C) Arrested at G-1 stage(D) Arrested at prophase
12. Plate meristem shows -
(A) Anticlinal divisions in two planes to right angle
to each other
(B) Anticlinal divisions in one plane
(C) Both periclinal & anticlinal divisions in one
plane
(D) Three dimensional divisions
13. Plastochron is -
(A) Period between initiation of two successive leaf
primordia
(B) Distance between two successive leaf primordia
(C) Region of origin of root branch
(D) Region of origin of stem branch
14. A parenchyma cell which stores ergastic materials
or waste substance is -
(A) Phragmoblast (B) Conidioblast
(C) Idioblast (D) Blastomere
15. The tissue not having specifically thickened walls
are -
(A) Parenchyma (B) Collenchyma
(C) Fibres (D) Sclereids
16. According to histogen concept of apical meristem,
three histogens are present. Which of the following
is differentiated from plerome
(A) Cortex (B) Xylem & Phloem
(C) Ground tissue system (D) Stele
17. Who differentiated tissue system in epidermal
tissue system, ground tissue system and vascular
tissue system -
(A) Hanstein (B) Buvet
(C) Sachs (D) Nageli
Exercise # 1 SINGLE OBJECTIVE NEET LEVEL
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PLANT ANATOMY
1. Laticiferous vessels are found in -
(A) Xylem tissue
(B) Phloem tissue
(C) Cortex
(D) None of the above
2. When phloem is completely surrounded by xylem,
the vascular bundle is called -
(A) Concentric, leptocentric/amphivasal
(B) Concentric, hadrocentric/amphicribral
(C) Conjoint, Collateral
(D) Conjoint, bicollateral
3. Amphivasal or leptocentric vascular bundles are
found is -
(A)Cycas and Dryopteris
(B) Dracaena
(C) Helianthus and Cucurbita
(D) Maize and Wheat
4. Callose can occur in -
(A) Phloem parenchyma
(B) Companion cells
(C) Sieve tubes
(D) Tracheids
5. A narrow thin-walled cell with large nucleus and
lying on the side of sieve tube is absent in
(A) Angiosperms (B) Pteridophytes
(C) Gymnosperms (D) Both (B) and (C)
6. An open collateral bundle is one in which -
(A) Xylem and phloem are separated by cambium
(B) Xylem and phloem lie side by side
(C) Cambium occurs on the outside of bundle
(D) Cambium does not occur in the bundle
7. Which is enucleate at maturity
(A) Sieve cell (B) Companion cell
(C) Cortical cell (D) Palisade cell
8. Longest fibres are found in -
(A) Jute (B) Cotton
(C) Sunn Hemp (D) Coir
9. Phloem tissue of angiosperms differs from that of
gymnosperms in having -
(A) Companion cells
(B) Sieve cells
(C) Sieve plates
(D) None of the above
10. A bundle with xylem and phloem separated by a
strip of cambium is -
(A) Collateral and closed
(B) Collateral and open
(C) Concentric and closed
(D) Bicollateral and open
11. Transport of water and dissolved minerals occurs
through -
(A) Phloem (B) Xylem
(C) Sieve tubes (D) Sclerenchyma
12. Which one of the following comprises only simple
tissues -
(A) Parenchyma, Collenchyma and Sclerenchyma
(B) Parenchyma, Xylem and Collenchyma
(C) Parenchyma, Xylem and Sclerenchyma
(D) Parenchyma, Xylem and Phloem
13. Vessel elements differ from other elements of xylem
in having -
(A) Simple and bordered pits on end walls
(B) Simple perforation on their end walls
(C) Simple pits on their radial walls
(D) Bordered pits on their lateral walls
14. Function of vessels is -
(A) Conduction of water and minerals
(B) Conduction of food
(C) Mechanical strength
(D) All of the above
SINGLE OBJECTIVE Exercise # 2 AIIMS LEVEL
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BIOLOGY FOR NEET & AIIMS
1. Match the following
Column-I Column-II
A. Hypodermis in dicot stem i. Absent
B. Pericycle in dicot stem ii. Parenchymatous
C. Ground tissue in monocot stem iii. Collenchymatous
D. Phloem parenchyma in monocot stem iv. Sclerenchymatous
(A) A-iv., B-i., C-ii., D-ii. (B) A-i., B-ii., C-iv., D-iii.
(C) A-iii., B-iv., C-ii., D-i. (D) A-ii., B-iii., C-i., D-iv.
2. Select a set having correct match
Dicot stem Monocot stem
A. Sclerenchymatous hypodermis Collenchymatous hypodermis
B. Parenchymatous pericycle Sclerenchymatous pericycle
C. Epidermis with trichomes Water containing cavities in vascular bundles
D. Oval bundles Wedge shaped bundles
3. Match the followings in column I with column II and choose the correct combination
Column -I Column -II
A. Xylem vessels i. Store food materials
B. Xylem trachieds ii. Obliterated lumen
C. Xylem fibre iii. Perforated plates
D. Xylem parenchyma iv. Chisel like ends
(A) A – iv, B – iii, C – ii, D – i (B) A – iii, B – ii, C – i, D – iv
(C) A – ii, B – i, C – iv, D – iii (D) A – i, B – ii, C – iii, D – iv
(D) A – iii, B – iv, C – ii, D – i
4. Match the items in Column – I with Column – II and choose the correct option
Column-I Column-II
A. Radial Vascular Bundle i. Cucurbita pepo
B. Collateral Vascular Bundle ii. Dracaena
C. Bicollateral Vascular Bundle iii. Roots of angiosperms
D. Amphicribal Bundle iv. Sunflower stem
E. Amphivasal Vascular Bundle v. Fern
5. Match the following and choose the correct option from below
Column - I Column –II
A. Meristem i. Photosynthesis, storage
B. Parenchyma ii. Mechanical support
C. Collenchyma iii. Actively dividing cells
D. Sclerenchyma iv. Stomata
E. Epidermal tissue v. Sclereids
Options :
(A) A-i, B-iii, C-v, D-ii, E-iv (B) A-iii, B-i, C-ii, D-v, E-iv
(C) A-ii, B-iv, C-v, D-i, E-iii (D) A-v, B-iv, C-iii, D-ii, E-i
Exercise # 3 PART - 1 MATRIX MATCH COLUMN
IIT-JEE | PRE-MEDICAL | CBSE | FOUNDATION
PLANT ANATOMY
1. What happens during vascularisation in plants ?
[CBSE AIPMT-2000]
(A) Differentiation of procambium is immediately followed
by the development of secondary xylem
and phloem
(B) Differentiation of procambium followed by the
development of xylem and phloem
(C) Differentiation of procambium, xylem and phloem
is simultaneous
(D) Differentiation of procambium followed by the
development of primary phloem and then by
primary xylem
2. Loading of phloem is related to -
[CBSE AIPMT-2001]
(A) increases of sugar in phloem
(B)Tracheids are multicellular with narrow lumen
(C) Vessels are unicellular with wide lumen
(D) Tracheids are unicellular with wide lumen
3. Which of the following statements is true ?
[CBSE AIPMT-2002]
(A) Vessels are multicellular with narrow lumen
(B) Tracheids are multicellular with narrow lumen
(C) Vessels are unicellular with wide lumen
(D) Tracheids are unicellular with wide lumen
4. Axillary bud and terminal bud are derived from the
activity of [CBSE AIPMT-2002]
(A) lateral meristem (B) intercalary meristem
(C) apical meristem (D) parenchyma
5. Four radial vacular bundles are found in
[CBSE AIPMT-2002]
(A) dicot root (B) monocot root
(C) dicot stem (D) monocot stem
6. Vessels are found in [CBSE AIPMT-2002]
(A) all angiosperms and some gymnosperms
(B) most of angiosperms and few gymnosperms
(C) all angiosperms and few gymnosperms and some
pteridophytes
(D) all pteridophytes
7. Main function of lenticel is [CBSE AIPMT-2002]
(A) transpiration (B) guttation
(C) gaseous exchange (D) bleeding
8. The cells of the quiescent centre are characterised
by [CBSE AIPMT-2003]
(A) dividing regularly to add to tunica
(B) having dense cytoplasm and prominent nuclei
(C) having light cytoplasm and small nuclei
(D) dividing regularly to add to the corpus
9. The apical meristem of the root is present
[CBSE AIPMT-2003]
(A) in all the roots
(B) only in radicals
(C) only in tap roots
(D) spore capsule of a moss
10. Chlorenchyma is known to develop in the
[CBSE AIPMT-2003]
(A) Pollen tube of Pinus
(B) cytoplasm of Chlorella
(C) mycelium of a green mould such as Aspergillus
(D) spore capsule of a moss
11. In a longitudinal section of root, starting from the
tip upward, the four zones occur in the following
order. [CBSE AIPMT-2004]
(A) root cap, cell division, cell enlargement, cell maturation
(B) root cap, cell division, cell maturation, cell enlargement
(C) cell division, cell enlargement, cell maturation,
root cap
(D) cell division, cell maturation, cell enlargement,
root cap
12. In a woody dicotyledonous tree which of the following
parts will mainly consist of primary tissues?
[CBSE AIPMT-2005]
(A) All parts
(B) Stem and root
(C) Flowers, fruits and leaves
(D) Shoot tips and root tips
13. A common structural feature of vessel elements and
sieve tube elements are [CBSE AIPMT-2006]
(A) pores on lateral walls
(B) presence of p-protein
(C) enucleate condition
(D) thick secondary walls
Exercise # 4 PART - 1 PREVIOUS YEAR (NEET/AIPMT)
IIT-JEE | PRE-MEDICAL | CBSE | FOUNDATION
BIOLOGY FOR NEET & AIIMS
1. Which of the following meristems are lateral meristems?
(A) Apical meristem, interfascicular cambium and cork cambium
(B) Fascicular vascular cambium, interfascicular cambium and cork cambium
(C) Apical meristem, intercalary meristem and cork cambium
(D) Intercalary meristem, interfascicular cambium and cork cambium
(E) Fascicular cambium, apical meristem and cork cambium
2. The increase in length of petiole results from the division of
(A) apical meristem (B) lateral meristem (C) intercalary meristem (D) phellogen
3. The girth or diameter of the stem increases due to the activity of the following.
(A) Apical meristems (B) Intercalary meristems (C) Lateral meristems (D) Parenchyma cells
4. Which one of the following is not a lateral meristem?
(A) Intrafascicular cambium (B) Interfascicular cambium
(C) Phellogen (D) Intercalary meristem
5. Which one of the following pairs is an example for lateral meristem?
(A) Procambium and phelloderm (B) Interfascicular cambium and phellem
(C) Phellogen and phelloderm (D) Phellogen and fascicular cambium
6. Which among these statements about collenchyma is true?
(A) Collenchyma cells are usually dead without protoplasts.
(B) The cells are long and narrow with thick lignified walls
(C) Collenchyma occurs in layers below the epidermis in dicotyledonous plants.
(D) These cells are found in the pulp of fruits like guava, pear and sapota.
(E) Collenchyma may be either fibres or sclereids.
7. Oval, spherical or polygonal cells, thickening at the corners due to deposition of cellulose, hemicellulose and pectin,
often containing chloroplasts and having or not having inter-cellular spaces are called
(A) parenchyma (B) chlorenchyma (C) sclerenchyma (D) collenchyma
8. Aerenchyma is found in
(A) epiphytes (B) hydrophytes (C) halophytes (D) xerophytes
9. Pick out the wrong statement.
(A) Gymnosperms lack vessels in their xylem.
(B) The cell wall of parenchyma is made up of pectin.
(C) The first formed primary xylem elements are called protoxylem.
(D) Gymnosperms have albuminous cells and have sieve cells in their phloem.
(E) Intercellular spaces are absent in collenchyma.
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