In dicot roots, secondary phloem is formed towards the _________ and secondary xylem is formed towards the __________ by the activity of vascular cambium.
periphery, centre
centre, periphery
innerside, outerside
Both B and C
There are _________types of medullary rays formed in dicot roots during secondary growth.
one
two
three
many
The common medullary rays between dicot stem and root is
primary medullary rays
secondary medullary rays
Both A and B
None of the above
Secondary growth occurs in
dicot root and stem of angiosperms
dicot root and stem of gymnosperms
monocot roots
Both 1 and 2
Lenticels are present in
stem only
root only
root, stem and leaf
The more correct function of the medullary rays in dicot roots are
water conduction only
food conduction only
food and water conduction
food and water conduction in radial direction
Which of the following is known as living mechanical tissue
parenchyma
collenchyma
sclerenchyma
All of the above
Which one is true of collenchyma?
forms the hypodermis of dicot stem
present below epidermis in layers or patches
thickened corners due to cellulose, hemicellulose, and pectin deposition
The main mechanical tissue of the plant is
Sclerenchyma is
dead and lignified
consists of long, narrow, thick walled cells
may be in the form of fibres and sclereids
All of these
Which one is true for sclereids
highly thickened dead walls with narrow lumen
present in fruit walls of nuts
pulp of guava, pear, and sapots
Sclerenchymatous fibres are
thick walled, elongated and pointed cells
contains simple and bordered pits
smallest cells in plant body
Which one is true regarding xylem?
vessels are absent in gymnosperms
cells of vessel are called vessel members
tracheid and vessel lack protoplasm
The elements of xylem which does food storage is
tracheids
vessels
xylem parenchyma
xylem fibres
In angiosperms, the main water transporting elements are
tracheids, vessels, xylem fibres, xylem parenchyma
The first formed primary xylem elements are__________and later formed is _____________
protoxylem , metaxylem
metaxylem , protoxylem
tracheids, vessels
The type of primary xylem when protoxylem lies towards the pith is known as
endarch
exarch
endoexarch
Both (1) and (3)
A mature sieve tube elements have
large vacuole
peripheral cytoplasm
lack nucleus
Pressure gradient in the sieve tubes is maintained by
companion cells
phloem fibres
phloem parenchyma
Which of the following is true for phloem parenchyma?
made up of elongated, tapering cylindrical cells
have dense cytoplasm and nucleus
stores food material and resins, latex and mucilage
Which element of the phloem becomes dead at maturity
sieve tube elements
Metaphloem contains _________sieve tubes while protophloem contains____________ sieve tubes.
bigger, narrow
narrow, bigger
narrow, no
no, bigger
Epidermal tissue system consists of
epidermal cells
stomata
trichomes, root hairs
Which one is true regarding epidermis?
usually single layered
made up of parenchymatous cells
outermost layer of the primary plant body
Stomata is a part of which type of tissue system
Epidermal tissue system
Ground tissue system
Vascular tissue system
Stomatal apparatus comprises of
stomatal aperture, guard cells
stomatal aperture, guard and subsidiary cells
stomatal aperture and guard, subsidiary and epidermal cells
stomatal aperture and subsidiary cells
In grasses, ____________cells are dumb-bell shaped
subsidiary cells
guard cells
stomatal apparatus
The epidermal hairs of root are usually _________while of shoots are usually________
unicellular, multicellular
multicellular, unicellular
multicellular, multicellular
unicellular, unicellular
Which of the following is true for trichomes
usually multicellular
may be branched or unbranched
prevent transpirational water loss
Which one is incorrect statement
subsidiary cells are specialised epidermal cells
cuticle is always present on epidermal tissue system
cuticle is absent in roots
Guard cells surround the stoma
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