What is present on the surface of the leaves which helps the plant prevent loss of water but is absent in roots?
Thick waxy layer called cuticle is present on the surface of the leaves which helps the plant to prevent loss of water. It is absent in roots.
Arrange the following in the sequence you would find them in a plant starting from the periphery – phellem, phellogen, phelloderm.
Protoxylem is the first formed xylem. If the protoxylem lies next to phloem what kind of arrangement of xylem would you call it?
Trunks of some of the aged tree species appear to be composed of several fused trunks. Is it a physiological or anatomical abnormality? Explain in detail.
Protoxylem is the first formed xylem. If the protoxylem lies next to phloem what kind of arrangement of xylem would you call it?
Cut a transverse section of young stem of a plant from your school garden and observe it under the microscope. How would you ascertain whether it is a monocot stem or a dicot stem ? Give reasons.
Plants require waterfortheir survival. But when watered excessively, plants die. Discuss.
While eating peach or pear it is usually seen that some stone like structures get entangled in the teeth, what are these stone like structures called?
Protoxylem is the first formed xylem. If the protoxylem lies next to phloem what kind of arrangement of xylem would you call it?
Match the following and choose the correct option from below.
| A. | Cuticle | (i) | Guard cells |
| B. | Bulliform cells | (ii) | Single layer |
| C. | Stomata | (iii) | Waxy layer |
| D. | Epidermis | (iv) | Empty colourless cell |
Options:
(a) A—(iii), B—(iv), C—(i), D—(ii)
(b) A—(i), B—(ii), C—(iii), D—(iv)
(c) A—(iii), B—(ii), C—(iv), D—(i)
(d) A—(iii), B—(ii), C—(i), D—(iv)
What is present on the surface of the leaves which helps the plant prevent loss of water but is absent in roots?
What are the characteristic differences found in the vascular tissue of gymnosperms and angiosperms?
Match the following and choose the correct option from below.
| 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)
Assume that a pencil box held in your hand, represents a plant cell. In how many possible planes can it be cut? Indicate these cuts with the help of line drawings.
A transverse section of the trunk of a tree shows concentric rings which are known as growth rings. How are these rings formed? What is the significance of these rings?
The transverse section of a plant material shows the following anatomical features – (a) the vascular bundles are conjoint, scattered and surrounded by a sclerenchymatous bundle sheath, (b) phloem parenchyma is absent. What will you identify it as?
The lawn grass (Cyandon dactylon) needs to be mowed frequently to prevent its overgrowth. Which tissue is responsible for its rapid growth?
Arrange the following in the sequence you would find them in a plant starting from the periphery – phellem, phellogen, phelloderm.
What are the characteristic differences found in the vascular tissue of gymnosperms and angiosperms?
Name the three basic tissue systems in the flowering plants. Give the tissue names under each system.
Explain the process of secondary growth in the stems of woody angiosperms with the help of schematic diagrams. What is its significance?
The transverse section of a plant material shows the following anatomical features – (a) the vascular bundles are conjoint, scattered and surrounded by a sclerenchymatous bundle sheath, (b) phloem parenchyma is absent. What will you identify it as?
Epidermal cells are often modified to perform specialized functions in plants. Name some of them and function they perform.
The lawn grass (Cynodon dactylon) needs to be mowed frequently to prevent its overgrowth. Which tissue is responsible for its rapid growth?
Assume that a pencil box held in your hand, represents a plant cell. In how many possible planes can it be cut? Indicate these cuts with the help of line drawings.
Deciduous plants shed their leaves during hot summer or in autumn. This process of shedding of leaves is called abscission. Apart from physiological changes what anatomical mechanism is involved in the abscission of leaves.
What part of the plant would show the following?
a. Radial vascular bundle
b. Polyarch xylem
c. Well developed pith
The cross-section of a plant material showed the following features when viewed under the microscope.
a. The vascular bundles were radially arranged.
b. Four xylem strands with exarch condition of protoxylem.
To which organ should it be assigned?
Plants require water for their survival. But when watered excessively, plants die. Discuss.