Grass leaves curl inwards during very dry weather. Select the most appropriate reason from the following :
1. Tyloses in vessels
2. Closure of stomata
3. Flaccidity of bulliform cells
4. Shrinkage of air spaces in spongy mesophyll
The entrance of minerals into the vascular cylinder in the dicot root is regulated by:
1. | epidermis | 2. | pericycle |
3. | endodermis | 4. | root hairs |
Given below is the diagram of a stomatal apparatus. In which of the following, all the four parts labelled as A, B, C and D are correctly identified:
A | B | C | D | |
1. | Guard cell | Stomatal aperture | Subsidiary Cell | Epidermal Cell |
2. | Epidermal Cell | Guard Cell | Stomatal aperture | Subsidiary cell |
3. | Epidermal Cell | Subsidiary Cell | Stomatal aperture | Guard Cell |
4. | Subsidiary Cell | Epidermal Cell | Guard Cell | Stomatal aperture |
To unlock all the explanations of this course, you need to be enrolled.
To unlock all the explanations of this course, you need to be enrolled.
The cross-section shown in the given diagram shows the structure of a:
1. | Monocot stem | 2. | Monocot root |
3. | Dicot root | 4. | Dicot stem |
To unlock all the explanations of this course, you need to be enrolled.
To unlock all the explanations of this course, you need to be enrolled.
Select the correct pair.
1. Cells of medullary rays that form part of a cambial ring - Interfascicular cambium
2. Loose parenchyma cells rupturing the epidermis and forming a lens-shaped opening in the bark - Spongy parenchyma
3. Large colorless empty cells in the epidermis of grass leaves - Subsidiary cells
4. In dicot leaves, vascular bundles are surrounded by large thick-walled cells - Conjunctive tissue
To unlock all the explanations of this course, you need to be enrolled.
To unlock all the explanations of this course, you need to be enrolled.
In which of the following pairs of parts of a flowering plant is epidermis absent?
1. | Root tip and shoot tip | 2. | Shoot bud and floral bud |
3. | Ovule and seed | 4. | Petiole and pedicel |
To unlock all the explanations of this course, you need to be enrolled.
To unlock all the explanations of this course, you need to be enrolled.
In the primary stems and roots, the type of cells usually present in cortex, pith and medullary rays is:
1. Parenchyma | 2. Collenchyma |
3. Sclerenchyma | 4. Meristem |
To unlock all the explanations of this course, you need to be enrolled.
To unlock all the explanations of this course, you need to be enrolled.
Regarding the guard cells:
1. | walls away from the stomatal pores are thin and those towards the stomatal pores are thick |
2. | walls away from the stomatal pores are thick and those towards the stomatal pores are thin |
3. | chloroplasts are mostly absent |
4. | play no role in the regulation of opening and closing of stomata |
To unlock all the explanations of this course, you need to be enrolled.
To unlock all the explanations of this course, you need to be enrolled.
Plants having little or no secondary growth are
1. | Grasses | 2. | Cycads |
3. | Conifers | 4. | Deciduous angiosperms |
Casparian strips occur in
1. Epidermis | 2. Endodermis |
3. Cortex | 4. Pericycle |
To unlock all the explanations of this course, you need to be enrolled.
To unlock all the explanations of this course, you need to be enrolled.