285777
Which of the following statements is not true about formation of annual rings in trees?
1 Differential activity of cambium causes light and dark bands of tissue early and late wood respectively.
2 Activity of cambium depends upon variation in climate.
3 Annual rings are nor prominent in tress of temperate region.
4 Annual ring is a combination of springwood and autumn wood produced in a year.
Explanation:
(c)The statement “annual rings are not prominent in tress of temperate region” is incorrect. Correct information about the statement is: Annual rings are formed due to the seasonal activity of cambium. In the plants of temperate region, cambium is highly active in spring and less active in autumn season. Hence, prominent rings are formed in these plants having light and dark bands of tissue. Rest of the statements about the formation of annual rings in trees are correct.
NCERT 93
Anatomy of Flowering Plants(NCERT)
285778
The correct sequence of different tissues of the periderm starting from periphery is
1 Phellogen Phellem Phelloderm
2 Phellem Phelloderm Phellogen
3 Phellem Phellogen Phelloderm
4 Phelloderm Phellogen Phellem
Explanation:
(c)In order to provide increase in girth and prevent harm or the rupturing of the outer ground tissues due to the formation of secondary vascular tissues, dicot stems produce a cork cambium or phellogen in the outer cortical cells. The cells of this phellogen divide periclinically to produce phellem or cork on the outer side and secondary cortex or phelloderm on the inner side. Phellem, phellogen, phelloderm collectively constitute periderm.
NCERT 96
Anatomy of Flowering Plants(NCERT)
285779
Secondary growth is absent in
1 dicot stem
2 gymnosperm
3 monocot stem
4 dicot root
Explanation:
(c)Vascular bundles are scattered and cambium is absent in monocot stem.
NCERT 97
Anatomy of Flowering Plants(NCERT)
285780
The presence of which of the following makes cork impervious to water in its cell wall?
1 Silica
2 Calcium carbonate
3 Suberin
4 Cuticle
Explanation:
(c)The phellem is dead, impervious to water because of suberin deposition in the cell wall. Cork prevents the con of water by evaporation. It protects the interior against entry of harmful microbes, mechanical injury and extremes of temperature. Cork is light compressible, nonreactive and sufficiently resistant to fire. It is used as stopper for bottles, shock absorption and insulation.
285777
Which of the following statements is not true about formation of annual rings in trees?
1 Differential activity of cambium causes light and dark bands of tissue early and late wood respectively.
2 Activity of cambium depends upon variation in climate.
3 Annual rings are nor prominent in tress of temperate region.
4 Annual ring is a combination of springwood and autumn wood produced in a year.
Explanation:
(c)The statement “annual rings are not prominent in tress of temperate region” is incorrect. Correct information about the statement is: Annual rings are formed due to the seasonal activity of cambium. In the plants of temperate region, cambium is highly active in spring and less active in autumn season. Hence, prominent rings are formed in these plants having light and dark bands of tissue. Rest of the statements about the formation of annual rings in trees are correct.
NCERT 93
Anatomy of Flowering Plants(NCERT)
285778
The correct sequence of different tissues of the periderm starting from periphery is
1 Phellogen Phellem Phelloderm
2 Phellem Phelloderm Phellogen
3 Phellem Phellogen Phelloderm
4 Phelloderm Phellogen Phellem
Explanation:
(c)In order to provide increase in girth and prevent harm or the rupturing of the outer ground tissues due to the formation of secondary vascular tissues, dicot stems produce a cork cambium or phellogen in the outer cortical cells. The cells of this phellogen divide periclinically to produce phellem or cork on the outer side and secondary cortex or phelloderm on the inner side. Phellem, phellogen, phelloderm collectively constitute periderm.
NCERT 96
Anatomy of Flowering Plants(NCERT)
285779
Secondary growth is absent in
1 dicot stem
2 gymnosperm
3 monocot stem
4 dicot root
Explanation:
(c)Vascular bundles are scattered and cambium is absent in monocot stem.
NCERT 97
Anatomy of Flowering Plants(NCERT)
285780
The presence of which of the following makes cork impervious to water in its cell wall?
1 Silica
2 Calcium carbonate
3 Suberin
4 Cuticle
Explanation:
(c)The phellem is dead, impervious to water because of suberin deposition in the cell wall. Cork prevents the con of water by evaporation. It protects the interior against entry of harmful microbes, mechanical injury and extremes of temperature. Cork is light compressible, nonreactive and sufficiently resistant to fire. It is used as stopper for bottles, shock absorption and insulation.
285777
Which of the following statements is not true about formation of annual rings in trees?
1 Differential activity of cambium causes light and dark bands of tissue early and late wood respectively.
2 Activity of cambium depends upon variation in climate.
3 Annual rings are nor prominent in tress of temperate region.
4 Annual ring is a combination of springwood and autumn wood produced in a year.
Explanation:
(c)The statement “annual rings are not prominent in tress of temperate region” is incorrect. Correct information about the statement is: Annual rings are formed due to the seasonal activity of cambium. In the plants of temperate region, cambium is highly active in spring and less active in autumn season. Hence, prominent rings are formed in these plants having light and dark bands of tissue. Rest of the statements about the formation of annual rings in trees are correct.
NCERT 93
Anatomy of Flowering Plants(NCERT)
285778
The correct sequence of different tissues of the periderm starting from periphery is
1 Phellogen Phellem Phelloderm
2 Phellem Phelloderm Phellogen
3 Phellem Phellogen Phelloderm
4 Phelloderm Phellogen Phellem
Explanation:
(c)In order to provide increase in girth and prevent harm or the rupturing of the outer ground tissues due to the formation of secondary vascular tissues, dicot stems produce a cork cambium or phellogen in the outer cortical cells. The cells of this phellogen divide periclinically to produce phellem or cork on the outer side and secondary cortex or phelloderm on the inner side. Phellem, phellogen, phelloderm collectively constitute periderm.
NCERT 96
Anatomy of Flowering Plants(NCERT)
285779
Secondary growth is absent in
1 dicot stem
2 gymnosperm
3 monocot stem
4 dicot root
Explanation:
(c)Vascular bundles are scattered and cambium is absent in monocot stem.
NCERT 97
Anatomy of Flowering Plants(NCERT)
285780
The presence of which of the following makes cork impervious to water in its cell wall?
1 Silica
2 Calcium carbonate
3 Suberin
4 Cuticle
Explanation:
(c)The phellem is dead, impervious to water because of suberin deposition in the cell wall. Cork prevents the con of water by evaporation. It protects the interior against entry of harmful microbes, mechanical injury and extremes of temperature. Cork is light compressible, nonreactive and sufficiently resistant to fire. It is used as stopper for bottles, shock absorption and insulation.
285777
Which of the following statements is not true about formation of annual rings in trees?
1 Differential activity of cambium causes light and dark bands of tissue early and late wood respectively.
2 Activity of cambium depends upon variation in climate.
3 Annual rings are nor prominent in tress of temperate region.
4 Annual ring is a combination of springwood and autumn wood produced in a year.
Explanation:
(c)The statement “annual rings are not prominent in tress of temperate region” is incorrect. Correct information about the statement is: Annual rings are formed due to the seasonal activity of cambium. In the plants of temperate region, cambium is highly active in spring and less active in autumn season. Hence, prominent rings are formed in these plants having light and dark bands of tissue. Rest of the statements about the formation of annual rings in trees are correct.
NCERT 93
Anatomy of Flowering Plants(NCERT)
285778
The correct sequence of different tissues of the periderm starting from periphery is
1 Phellogen Phellem Phelloderm
2 Phellem Phelloderm Phellogen
3 Phellem Phellogen Phelloderm
4 Phelloderm Phellogen Phellem
Explanation:
(c)In order to provide increase in girth and prevent harm or the rupturing of the outer ground tissues due to the formation of secondary vascular tissues, dicot stems produce a cork cambium or phellogen in the outer cortical cells. The cells of this phellogen divide periclinically to produce phellem or cork on the outer side and secondary cortex or phelloderm on the inner side. Phellem, phellogen, phelloderm collectively constitute periderm.
NCERT 96
Anatomy of Flowering Plants(NCERT)
285779
Secondary growth is absent in
1 dicot stem
2 gymnosperm
3 monocot stem
4 dicot root
Explanation:
(c)Vascular bundles are scattered and cambium is absent in monocot stem.
NCERT 97
Anatomy of Flowering Plants(NCERT)
285780
The presence of which of the following makes cork impervious to water in its cell wall?
1 Silica
2 Calcium carbonate
3 Suberin
4 Cuticle
Explanation:
(c)The phellem is dead, impervious to water because of suberin deposition in the cell wall. Cork prevents the con of water by evaporation. It protects the interior against entry of harmful microbes, mechanical injury and extremes of temperature. Cork is light compressible, nonreactive and sufficiently resistant to fire. It is used as stopper for bottles, shock absorption and insulation.
