Main function of lenticel is
transpiration
guttation
gaseous exchange
both (a) & (c)
Correct Answer :
A. transpiration
Lenticels are some loosely arranged areas in the periderm. Formed due to rapid activity of phellogen. Lenticels are characteristics of woody stem. They help in gaseous exchange and transpiration.
Related Questions
Identify A, B and C in the given figure of shoot apical meristem
A Leaf primordium, B Shoot apical meristem, C Axillary bud
A Leaf primordium, B Shoot apical meristem, C Apical bud
A Root hair primordium, B Root apical meristem, C Axillary bud
A Root hair primordium, B Root apical meristem, C Terminal bud
Cells of permanent tissues are specialized
functionally.
only structurally.
both structurally and functionally.
for mitosis.
The apical meristem of the root is present
in all the roots.
only in radicals.
only in tap roots.
only in adventitious roots.
As secondary growth proceeds, in a dicot stem, the thickness of
sapwood increases.
heartwood increase.
both sapwood and heartwood increases.
both sapwood and heartwood remains the same.
A student was given a tissue to observe under the microscope. He observes the tissue and concludes that the tissue is a type of simple plant tissue and provides mechanical support to young stem and petiole of leaf.
Identify the tissue.
Parenchyma
Collenchyma
Sclerenchyma
Xylem parenchyma
During the formation of leaves and elongation of stem, some cells left behind from the shoot apical meristem, constitute the
lateral meristem
axillary bud
cork cambium
fascicular cambium
Match the terms given in column I with their features given in column II and choose the correct option.
| Column-I | Column-II |
|---|---|
| (Terms) | (Features) |
| A. Fibres | (i) Cells are living and thin walled with cellulosic cell wall, store food materials in the form of starch or fat |
| B. Sclereids | (ii) Main water conductive cells of the pteridophytes and the gymnosperms |
| C. Tracheids | (iii) Thick walled, elongated and pointed cells, generally occurring in groups |
| D. Vessels | (iv) Long cylindrical tube like structure and cells are devoid of protoplasm. Characteristic feature of angiosperms |
| E. Xylem parenchyma | (v) Reduced form of sclerenchyma cells with highly thickened lignified cellular walls that form small bundles of durable layers of tissue in most plants. |
A - (i), B - (ii), C - (iii), D - (iv), E - (v)
A - (iii), B - (v), C - (ii), D - (iv), E - (i)
A - (iii), B - (i), C - (v), D - (ii), E - (iv)
A - (v), B - (iv), C - (iii), D - (i), E - (ii)
Identify the types of simple tissue indicated by A, B, C and D and their function.
A Parenchyma, Photosynthesis, Storage and Secretion.
B Sclerenchyma Scleriods; Transport food material
C Collenchyma; Provides mechanical support to organs.
D Sclerenchyma Fibres; Provide Mechanical support to the growing parts of the plant such as young stem and petiole of a leaf.
Which of the following is responsible for the formation of an embryonic shoot called axillary bud?
Lateral meristem
Apical meristem
Intercalary meristem
Both
A plant tissue when stained showed the presence of hemicellulose and pectin in cells wall of its cells. The tissue is called
collenchyma
sclerenchyma
xylem
meristem
Which of following helps bamboo and grasses to elongate ?
Apical meristems
Lateral meristems
Secondary meristems
Intercalary meristems
Which one of the following option shows the correct labelling of the parts marked as A, B, C and D in the given figure of a typical dicot root?
A Primary phloem, B Vascular cambium, C Secondary phloem, D Primary xylem
A Secondary phloem, B Vascular cambium, C Primary phloem, D Primary xylem
A Primary phloem, B Primary xylem, C Secondary phloem, D Vascular cambium
A Secondary phloem, B Primary xylem, C Primary phloem, D Vascular cambium
Which of the following are present in monocot root ?
conjoint, collateral, open polyarch vascular bundle.
exodermis, endarch, tetrarch closed vascular bundles.
suberized exodermis, casparian strip, passage cells, cambium.
suberized exodermis, polyarch xylem, pith.
In the given figure of phloem tissue, identify the marked part (A, B and C) which help in maintaining the pressure gradient
in the sieve tubes.
A
B
C
None of the above
Which of the following pair of match is not correct?
Pith - Large and well developed in monocotyledonous root.
Root hairs - Helps in preventing water loss due to transpiration
Sieve tube elements - Its functions are controlled by the nucleus of companion cells.
Stomatal apparatus - Consists of stomatal aperture, guard cells and surrounding subsidiary cells
A piece of wood having no vessels (trachea) must be belonged to
teak
mango
pine
palm
Sclerenchyma usually___________and_____________ protoplasts.
live, without
dead, with
live, with
dead, without
Phellogen and phellem respectively denote
cork and cork cambium,
cork cambium and cork,
secondary cortex and cork,
cork and secondary cortex,
Match the followings and choose the correct option
| Column-I | Column-II |
|---|---|
| A. Cuticle | I. Guard cells |
| B. Bulliform cells | II. Outer layer |
| C. Stomata | III. Waxy layer |
| D. Epidermis | IV. Empty colourless cell |
A III, B IV, C I, D II
A I, B II, C III, D IV
A III, B II, C IV, D I
A III, B II, C I, D IV
A common structural feature of vessel elements and sieve tube elements are
pores on lateral walls.
presence of p-protein.
enucleate condition.
thick secondary walls.
Lignin is the important constituent in the cell wall of
phloem
parenchyma
xylem
cambium
A narrow layer of thin walled cells found between phloem/ bark and wood of a dicot is
cork cambium
vascular cambium
endodermis
both (a) & (c)
Match the names of the structures given in column-I with the functions given in column-II, choose the answer which gives the correct combination of the two columns :
| Column-I | Column-II |
|---|---|
| (Structure) | (Function) |
| A. Stomata | I. Protection of stem |
| B. Bark | II. Plant movement |
| C. Cambium | III. Secondary growth |
| D. Cuticle | IV. Transpiration |
| V. Prevent the loss of water | ... |
A V, B III, C I, D IV
A I, B IV, C V, D III
A II, B IV, C I, D III
A IV, B I, C III, D V
Cork is formed from
phellogen
vascular cambium
phloem
xylem
The trees growing in desert will
show alternate rings of xylem and sclerenchyma.
have only conjunctive tissue and phloem is formed by the activity of cambium.
show distinct annual rings.
not show distinct annual rings.
The given diagrams show stomatal apparatus in dicots and monocots. Which one is correct option for A, B and C?
A Epidermal cells; B Subsidiary cells; C chloroplast
A Guard cells; B Subsidiary cells; C Stomatal pore
A Guard cells; B Epidermal cells; C Guard cells
A Epidermal cells; B Subsidiary cells; C Guard cells
In an experiment, a student cut a transverse section of young stem of a plant which he has taken from his school garden.
After observing it under the microscope how would he ascertain whether it is a monocot stem or a dicot stem?
With the help of bulliform cells.
With the help of casparian strips.
With the help of vascular bundles.
With the help of stomatal apparatus.
Identify types of vascular bundles in given figures A, B and C.
Radial; Conjoint closed; Conjoint open
Conjoint closed; Conjoint open; Radial
Conjoint open; Conjoint closed; Radial
Bicollateral; Concentric; Radial
Read the following statements and answer the question.
- It has a sclerenchymatous hypodermis, a large number of scattered vascular bundles and a large parenchymatous ground tissue.
- Vascular bundles are conjoint and closed.
- Peripheral vascular bundles are generally smaller than the centrally located ones.
- Phloem parenchyma is absent, and water- containing cavities are present within the vascular bundles.
Which plant anatomy is being described by the above statements?
Dicotyledonous root
Monocotyledonous root
Dicotyledonous stem
Monocotyledonous stem
Cork cambium and vascular cambium are
the parts of secondary xylem and phloem.
the parts of pericycle.
lateral meristems.
apical meristems.