259854
An immature male gametophyte differs from a mature male gametophyte in that it
1 has not yet left the pollen sac
2 has not yet germinated and its generative cell has not divided into two male gamete
3 is a microspore that has not yet divided by mitosis
4 still consist of microsporocyte
Explanation:
The pollen is immature or partially developed male gametophyte similarly, the unicellular microspore produce male gametes and develops into mature microgametophyte by the process of mitotic cell division. Hence the pollen grains are immature male gametophyte and partially developed male gametophyte. An immature male gametophyte differs from a mature male gametophyte in that it has not got germinated. At the maturity the male gametophyte consists of three cells, vegetative cell and two sperm cell.
AMU-2014
Plant kingdom
259857
Which one of the following is considered important in the development of seed habit?
1 Free-living gametophyte
2 Dependent sporophyte
3 Heterospory
4 Haplontic life cycle
Explanation:
Heterospory is thus considered an important step in evolunton as it is a precursor to the seed habit. Heterospory evolved first in pteridophytes such as Selaginella and Salvinia. The seed habit is the most complex and evolutionary method of sexual reproduction.
AIPMT-2009
Plant kingdom
259859
Heterospory is the production of
1 sexual and asexual spores
2 large and small spores
3 haploid and diploid spores
4 diploid and tetraploid spores
Explanation:
Heterospory is the production of spores of two different size and sexes by the sporophytes of land plant. In some pteridophytes two type of spores are formed which differ significantly in their size and also in function. This phenomenon is called heterospory example- Selaginella and Marsilea etc.
JIPMER-2004
Plant kingdom
259863
In the prothallus of a vascular cryptogam, the antherozoids and eggs mature at different times. As a result:
1 Self fertilization is prevented
2 There is no change in success rate of fertilization
3 There is high degree of sterility
4 One can conclude that the plant is apomictic
Explanation:
In prothallus of vascular cryptogams, the antherozoids and egg mature at different times and is called as an outbreeding divce. The antherozoids are biflagellated or multiflagellated. As a result, of which self-fertilization is prevented and cross fertilization occurs.
259854
An immature male gametophyte differs from a mature male gametophyte in that it
1 has not yet left the pollen sac
2 has not yet germinated and its generative cell has not divided into two male gamete
3 is a microspore that has not yet divided by mitosis
4 still consist of microsporocyte
Explanation:
The pollen is immature or partially developed male gametophyte similarly, the unicellular microspore produce male gametes and develops into mature microgametophyte by the process of mitotic cell division. Hence the pollen grains are immature male gametophyte and partially developed male gametophyte. An immature male gametophyte differs from a mature male gametophyte in that it has not got germinated. At the maturity the male gametophyte consists of three cells, vegetative cell and two sperm cell.
AMU-2014
Plant kingdom
259857
Which one of the following is considered important in the development of seed habit?
1 Free-living gametophyte
2 Dependent sporophyte
3 Heterospory
4 Haplontic life cycle
Explanation:
Heterospory is thus considered an important step in evolunton as it is a precursor to the seed habit. Heterospory evolved first in pteridophytes such as Selaginella and Salvinia. The seed habit is the most complex and evolutionary method of sexual reproduction.
AIPMT-2009
Plant kingdom
259859
Heterospory is the production of
1 sexual and asexual spores
2 large and small spores
3 haploid and diploid spores
4 diploid and tetraploid spores
Explanation:
Heterospory is the production of spores of two different size and sexes by the sporophytes of land plant. In some pteridophytes two type of spores are formed which differ significantly in their size and also in function. This phenomenon is called heterospory example- Selaginella and Marsilea etc.
JIPMER-2004
Plant kingdom
259863
In the prothallus of a vascular cryptogam, the antherozoids and eggs mature at different times. As a result:
1 Self fertilization is prevented
2 There is no change in success rate of fertilization
3 There is high degree of sterility
4 One can conclude that the plant is apomictic
Explanation:
In prothallus of vascular cryptogams, the antherozoids and egg mature at different times and is called as an outbreeding divce. The antherozoids are biflagellated or multiflagellated. As a result, of which self-fertilization is prevented and cross fertilization occurs.
259854
An immature male gametophyte differs from a mature male gametophyte in that it
1 has not yet left the pollen sac
2 has not yet germinated and its generative cell has not divided into two male gamete
3 is a microspore that has not yet divided by mitosis
4 still consist of microsporocyte
Explanation:
The pollen is immature or partially developed male gametophyte similarly, the unicellular microspore produce male gametes and develops into mature microgametophyte by the process of mitotic cell division. Hence the pollen grains are immature male gametophyte and partially developed male gametophyte. An immature male gametophyte differs from a mature male gametophyte in that it has not got germinated. At the maturity the male gametophyte consists of three cells, vegetative cell and two sperm cell.
AMU-2014
Plant kingdom
259857
Which one of the following is considered important in the development of seed habit?
1 Free-living gametophyte
2 Dependent sporophyte
3 Heterospory
4 Haplontic life cycle
Explanation:
Heterospory is thus considered an important step in evolunton as it is a precursor to the seed habit. Heterospory evolved first in pteridophytes such as Selaginella and Salvinia. The seed habit is the most complex and evolutionary method of sexual reproduction.
AIPMT-2009
Plant kingdom
259859
Heterospory is the production of
1 sexual and asexual spores
2 large and small spores
3 haploid and diploid spores
4 diploid and tetraploid spores
Explanation:
Heterospory is the production of spores of two different size and sexes by the sporophytes of land plant. In some pteridophytes two type of spores are formed which differ significantly in their size and also in function. This phenomenon is called heterospory example- Selaginella and Marsilea etc.
JIPMER-2004
Plant kingdom
259863
In the prothallus of a vascular cryptogam, the antherozoids and eggs mature at different times. As a result:
1 Self fertilization is prevented
2 There is no change in success rate of fertilization
3 There is high degree of sterility
4 One can conclude that the plant is apomictic
Explanation:
In prothallus of vascular cryptogams, the antherozoids and egg mature at different times and is called as an outbreeding divce. The antherozoids are biflagellated or multiflagellated. As a result, of which self-fertilization is prevented and cross fertilization occurs.
259854
An immature male gametophyte differs from a mature male gametophyte in that it
1 has not yet left the pollen sac
2 has not yet germinated and its generative cell has not divided into two male gamete
3 is a microspore that has not yet divided by mitosis
4 still consist of microsporocyte
Explanation:
The pollen is immature or partially developed male gametophyte similarly, the unicellular microspore produce male gametes and develops into mature microgametophyte by the process of mitotic cell division. Hence the pollen grains are immature male gametophyte and partially developed male gametophyte. An immature male gametophyte differs from a mature male gametophyte in that it has not got germinated. At the maturity the male gametophyte consists of three cells, vegetative cell and two sperm cell.
AMU-2014
Plant kingdom
259857
Which one of the following is considered important in the development of seed habit?
1 Free-living gametophyte
2 Dependent sporophyte
3 Heterospory
4 Haplontic life cycle
Explanation:
Heterospory is thus considered an important step in evolunton as it is a precursor to the seed habit. Heterospory evolved first in pteridophytes such as Selaginella and Salvinia. The seed habit is the most complex and evolutionary method of sexual reproduction.
AIPMT-2009
Plant kingdom
259859
Heterospory is the production of
1 sexual and asexual spores
2 large and small spores
3 haploid and diploid spores
4 diploid and tetraploid spores
Explanation:
Heterospory is the production of spores of two different size and sexes by the sporophytes of land plant. In some pteridophytes two type of spores are formed which differ significantly in their size and also in function. This phenomenon is called heterospory example- Selaginella and Marsilea etc.
JIPMER-2004
Plant kingdom
259863
In the prothallus of a vascular cryptogam, the antherozoids and eggs mature at different times. As a result:
1 Self fertilization is prevented
2 There is no change in success rate of fertilization
3 There is high degree of sterility
4 One can conclude that the plant is apomictic
Explanation:
In prothallus of vascular cryptogams, the antherozoids and egg mature at different times and is called as an outbreeding divce. The antherozoids are biflagellated or multiflagellated. As a result, of which self-fertilization is prevented and cross fertilization occurs.
