262532
Which one of the following statements is not true
1 Stored pollen in liquid nitrogen can be used in the crop breeding programmes
2 Tapetum helps in the dehiscence of anther
3 Exine of pollen grains is made up of sporopollenin
4 Pollen grains of many species causes severe allergies
Explanation:
Tapetum is the inner most layer of the anther wall and completely surrounds the sporogenous tissue. It is usually single layered and has a several nutritive and secretary functions related to pollen development, pollination and pollen germination.
NEET-2016 Phase-I
Sexual Reproduction in Flowering Plants
262533
An organic substance that can stand with environmental extremes and cannot be degraded by any other enzyme is:
1 Lignin
2 Cellulose
3 Cuticle
4 Sporopollenin
Explanation:
Sporopollenin forms the outer covering of the exine and it is the most resistant organic material on the earth ever known. Sporopollenin is one of the most chemically inert biological polymers. It protect the pollen grains form external factors such as temperature, acid alkali, enzyme etc. Sporopollenin is also found in the cell walls of several taxa of green algae including phycobillins and chlorella.
AIPMT (Screening)-2012
Sexual Reproduction in Flowering Plants
262534
Which of the following statements is correct?
1 Sporopollenin can withstand high temperatures but not strong acids
2 Sporopollenin can be degraded by enzymes
3 Sporopollenin is made up of inorganic materials
4 Sporopollenin can withstand high temperatures as well as strong acids and alkalis
Explanation:
Sporopollenin is a ubiquitous and extremely chemically inert biopolymer that constitutes the outer wall of all land plant spores and pollen grains. Sporopollenin protects the vulnerable plant gametes against a wide range of environmental assaults. - The exact composition of sporopollenin is not known but analyses and studies have revealed that it is composed of long chain fatty acids along with some other biopolymers like phenolics and corotenoids.
NEET (Karnataka)-2013
Sexual Reproduction in Flowering Plants
262535
There are 10 flowers in one individual plant of Crotalaria. In each microsporangium of every stamen of all the flowers, there are 30 microspore mother cells. How many pollen gains are formed from that plant?
1 4,000
2 10,000
3 24,000
4 48,000
Explanation:
Crotalaria is a member of Papilinaceae, in which 10 stamens are present in flower. Each stamen has 4 micro-sporangia, (i.e. \(10 \times 4=40\) ) in which microspore mother cell are found. Each microspore mother cell gives rise to a pollen tetrad (i.e. \(40 \times 4=\) 160 ), for 1 flower having 30 micro-sporangia it would be \((160 \times 30=4800)\) pollen grain. Thus' we have to calculate for 10 flowers then it would be \((4800 \times 10=\) 48000) pollen grain. In this family flower is bisexual, strongly zygomorphic, perigynous, pentamerous, cyclic, bracteates, bracteolate with papilionaceous corolla.
NEET Test Series from KOTA - 10 Papers In MS WORD
WhatsApp Here
Sexual Reproduction in Flowering Plants
262532
Which one of the following statements is not true
1 Stored pollen in liquid nitrogen can be used in the crop breeding programmes
2 Tapetum helps in the dehiscence of anther
3 Exine of pollen grains is made up of sporopollenin
4 Pollen grains of many species causes severe allergies
Explanation:
Tapetum is the inner most layer of the anther wall and completely surrounds the sporogenous tissue. It is usually single layered and has a several nutritive and secretary functions related to pollen development, pollination and pollen germination.
NEET-2016 Phase-I
Sexual Reproduction in Flowering Plants
262533
An organic substance that can stand with environmental extremes and cannot be degraded by any other enzyme is:
1 Lignin
2 Cellulose
3 Cuticle
4 Sporopollenin
Explanation:
Sporopollenin forms the outer covering of the exine and it is the most resistant organic material on the earth ever known. Sporopollenin is one of the most chemically inert biological polymers. It protect the pollen grains form external factors such as temperature, acid alkali, enzyme etc. Sporopollenin is also found in the cell walls of several taxa of green algae including phycobillins and chlorella.
AIPMT (Screening)-2012
Sexual Reproduction in Flowering Plants
262534
Which of the following statements is correct?
1 Sporopollenin can withstand high temperatures but not strong acids
2 Sporopollenin can be degraded by enzymes
3 Sporopollenin is made up of inorganic materials
4 Sporopollenin can withstand high temperatures as well as strong acids and alkalis
Explanation:
Sporopollenin is a ubiquitous and extremely chemically inert biopolymer that constitutes the outer wall of all land plant spores and pollen grains. Sporopollenin protects the vulnerable plant gametes against a wide range of environmental assaults. - The exact composition of sporopollenin is not known but analyses and studies have revealed that it is composed of long chain fatty acids along with some other biopolymers like phenolics and corotenoids.
NEET (Karnataka)-2013
Sexual Reproduction in Flowering Plants
262535
There are 10 flowers in one individual plant of Crotalaria. In each microsporangium of every stamen of all the flowers, there are 30 microspore mother cells. How many pollen gains are formed from that plant?
1 4,000
2 10,000
3 24,000
4 48,000
Explanation:
Crotalaria is a member of Papilinaceae, in which 10 stamens are present in flower. Each stamen has 4 micro-sporangia, (i.e. \(10 \times 4=40\) ) in which microspore mother cell are found. Each microspore mother cell gives rise to a pollen tetrad (i.e. \(40 \times 4=\) 160 ), for 1 flower having 30 micro-sporangia it would be \((160 \times 30=4800)\) pollen grain. Thus' we have to calculate for 10 flowers then it would be \((4800 \times 10=\) 48000) pollen grain. In this family flower is bisexual, strongly zygomorphic, perigynous, pentamerous, cyclic, bracteates, bracteolate with papilionaceous corolla.
262532
Which one of the following statements is not true
1 Stored pollen in liquid nitrogen can be used in the crop breeding programmes
2 Tapetum helps in the dehiscence of anther
3 Exine of pollen grains is made up of sporopollenin
4 Pollen grains of many species causes severe allergies
Explanation:
Tapetum is the inner most layer of the anther wall and completely surrounds the sporogenous tissue. It is usually single layered and has a several nutritive and secretary functions related to pollen development, pollination and pollen germination.
NEET-2016 Phase-I
Sexual Reproduction in Flowering Plants
262533
An organic substance that can stand with environmental extremes and cannot be degraded by any other enzyme is:
1 Lignin
2 Cellulose
3 Cuticle
4 Sporopollenin
Explanation:
Sporopollenin forms the outer covering of the exine and it is the most resistant organic material on the earth ever known. Sporopollenin is one of the most chemically inert biological polymers. It protect the pollen grains form external factors such as temperature, acid alkali, enzyme etc. Sporopollenin is also found in the cell walls of several taxa of green algae including phycobillins and chlorella.
AIPMT (Screening)-2012
Sexual Reproduction in Flowering Plants
262534
Which of the following statements is correct?
1 Sporopollenin can withstand high temperatures but not strong acids
2 Sporopollenin can be degraded by enzymes
3 Sporopollenin is made up of inorganic materials
4 Sporopollenin can withstand high temperatures as well as strong acids and alkalis
Explanation:
Sporopollenin is a ubiquitous and extremely chemically inert biopolymer that constitutes the outer wall of all land plant spores and pollen grains. Sporopollenin protects the vulnerable plant gametes against a wide range of environmental assaults. - The exact composition of sporopollenin is not known but analyses and studies have revealed that it is composed of long chain fatty acids along with some other biopolymers like phenolics and corotenoids.
NEET (Karnataka)-2013
Sexual Reproduction in Flowering Plants
262535
There are 10 flowers in one individual plant of Crotalaria. In each microsporangium of every stamen of all the flowers, there are 30 microspore mother cells. How many pollen gains are formed from that plant?
1 4,000
2 10,000
3 24,000
4 48,000
Explanation:
Crotalaria is a member of Papilinaceae, in which 10 stamens are present in flower. Each stamen has 4 micro-sporangia, (i.e. \(10 \times 4=40\) ) in which microspore mother cell are found. Each microspore mother cell gives rise to a pollen tetrad (i.e. \(40 \times 4=\) 160 ), for 1 flower having 30 micro-sporangia it would be \((160 \times 30=4800)\) pollen grain. Thus' we have to calculate for 10 flowers then it would be \((4800 \times 10=\) 48000) pollen grain. In this family flower is bisexual, strongly zygomorphic, perigynous, pentamerous, cyclic, bracteates, bracteolate with papilionaceous corolla.
262532
Which one of the following statements is not true
1 Stored pollen in liquid nitrogen can be used in the crop breeding programmes
2 Tapetum helps in the dehiscence of anther
3 Exine of pollen grains is made up of sporopollenin
4 Pollen grains of many species causes severe allergies
Explanation:
Tapetum is the inner most layer of the anther wall and completely surrounds the sporogenous tissue. It is usually single layered and has a several nutritive and secretary functions related to pollen development, pollination and pollen germination.
NEET-2016 Phase-I
Sexual Reproduction in Flowering Plants
262533
An organic substance that can stand with environmental extremes and cannot be degraded by any other enzyme is:
1 Lignin
2 Cellulose
3 Cuticle
4 Sporopollenin
Explanation:
Sporopollenin forms the outer covering of the exine and it is the most resistant organic material on the earth ever known. Sporopollenin is one of the most chemically inert biological polymers. It protect the pollen grains form external factors such as temperature, acid alkali, enzyme etc. Sporopollenin is also found in the cell walls of several taxa of green algae including phycobillins and chlorella.
AIPMT (Screening)-2012
Sexual Reproduction in Flowering Plants
262534
Which of the following statements is correct?
1 Sporopollenin can withstand high temperatures but not strong acids
2 Sporopollenin can be degraded by enzymes
3 Sporopollenin is made up of inorganic materials
4 Sporopollenin can withstand high temperatures as well as strong acids and alkalis
Explanation:
Sporopollenin is a ubiquitous and extremely chemically inert biopolymer that constitutes the outer wall of all land plant spores and pollen grains. Sporopollenin protects the vulnerable plant gametes against a wide range of environmental assaults. - The exact composition of sporopollenin is not known but analyses and studies have revealed that it is composed of long chain fatty acids along with some other biopolymers like phenolics and corotenoids.
NEET (Karnataka)-2013
Sexual Reproduction in Flowering Plants
262535
There are 10 flowers in one individual plant of Crotalaria. In each microsporangium of every stamen of all the flowers, there are 30 microspore mother cells. How many pollen gains are formed from that plant?
1 4,000
2 10,000
3 24,000
4 48,000
Explanation:
Crotalaria is a member of Papilinaceae, in which 10 stamens are present in flower. Each stamen has 4 micro-sporangia, (i.e. \(10 \times 4=40\) ) in which microspore mother cell are found. Each microspore mother cell gives rise to a pollen tetrad (i.e. \(40 \times 4=\) 160 ), for 1 flower having 30 micro-sporangia it would be \((160 \times 30=4800)\) pollen grain. Thus' we have to calculate for 10 flowers then it would be \((4800 \times 10=\) 48000) pollen grain. In this family flower is bisexual, strongly zygomorphic, perigynous, pentamerous, cyclic, bracteates, bracteolate with papilionaceous corolla.
