Identify the correct statement regarding collenchymas in plants:-
1. | They occur in layers below the epidermis of monocotyledonous plants. |
2. | Cells are much thickened at the corners due to the deposition of lignin. |
3. | Collenchymatous cells do not contain chloroplasts. |
4. | They provide mechanical strength to the growing parts of the plant. |
What is the number of correct statements amongst the following regarding the phloem tissue of plants?
I. Gymnosperms lack albuminous cells and sieve cells.
II. The companion cells are specialized parenchymatous cells.
III. Phloem parenchyma is absent in most of the monocotyledons.
IV. Phloem fibers are generally absent in the primary phloem.
1. 0
2. 2
3. 3
4. 4
In dicot roots, the initiation of the lateral roots and the vascular cambium during the secondary growth takes place in:
1. Pericycle
2. Endodermis
3. Conjuctive tissue
4. Epidermis
In dicot stem the vascular bundle is:-
1. Conjoint, open and with exarch protoxylem.
2. Conjoint, open and with endarch protoxylem.
3. Conjoint and closed.
4. Scattered, each surrounded by a sclerenchymatous bundle sheath.
Bulliform cells:
1. Are found in dorsiventral leaves and help in photosynthesis.
2. Are found in dorsiventral leaves and help in minimizing water loss.
3. Are found in isobilatetral leaves and help in minimizing water loss.
4. Are found in isobilatetral leaves and help in photosynthesis.
During secondary growth in the stem:-
1. The amount of secondary xylem produced is more than the secondary phloem as the
cambium is generally more active on the inner side than the outer.
2. the amount of secondary phloem produced is more than the secondary xylem as the cambium is generally more active on the inner side than the outer.
3. the amount of secondary xylem produced is more than the secondary phloem as the cambium is generally more active on the outer side than the inner.
4. the amount of secondary phloem produced is more than the secondary xylem as the cambium is generally more active on the outer side than the inner.
In temperate region plants, the wood with fewer xylary elements and narrow vessels, is termed as:-
1. Spring wood
2. Autumn wood
3. Sap wood
4. Heart wood
The term 'bark' includes:
I. Phellogen
II. Phellem
III. Phelloderm
IV. Secondary phloem
1. I, II and III only
2. I, II and IV only
3. II, III and IV only
4. I, II, III and IV only
Identify the incorrect statement:
1. The presence of vessels is a characteristic of angiosperms
2. In roots the primary xylem is exarch
3. Gymnosperms lack albuminous cells and sieve cells
4. Bast fibers are generally absent in primary phloem
Parts of grasses removed by the grazing herbivores are regenerated due to the activity of:
1. Apical meristem
2. Intercalary meristem
3. Interfascicular cambium
4. Fascicular vascular cambium