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question_answer1)
After demonstration of totipotency, a botanist wishes to produce identical plants from an angiosperm by tissue culture. The parts or tissues which are likely to yield haploid embryos are
A)
Root tips done
clear
B)
Stem apices done
clear
C)
Leaves done
clear
D)
Anthers done
clear
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question_answer2)
The most significant value of vegetative propagation is that
A)
It is a means of producing a large population of individuals genetically identical to the parent done
clear
B)
It ensures that the progeny are safe from attack of diseases and pests done
clear
C)
It is an ancient practice done
clear
D)
It enables rapid production of genetic variation done
clear
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question_answer3)
The microspore tetrad of angiosperm at the time of formation, are surrounded by a callose wall. Breakdown of this wall is brought about by the enzyme callase synthesized by the
A)
Tetrad cytoplasm done
clear
B)
Ribosome of the tetrad done
clear
C)
Spore mother cells done
clear
D)
Cells of tapetum done
clear
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question_answer4)
In angiosperms, the following events occur during megasporogenesis and megagametogenesis (i) Differentiation of megaspore mother cells (ii) Meiosis of the megaspore mother cell (iii) Formation of a linear tetrad (iv) Mitotic division of the functional megaspore (v) Degeneration of 3 megaspores (vi) Formation of embryo sac (vii) Fusion of polar nuclei The correct sequence is
A)
v, i, ii, vi, vii, iii, iv done
clear
B)
iv, iii, vii, vi, ii, i, v done
clear
C)
v, i, ii, vii, vi, iv, iii done
clear
D)
v, i, ii, vi, vii, iv, iii done
clear
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question_answer5)
Cotton plug like tissue present at the mouth of the micropyle responsible for directing the pollen tube is called
A)
Carpophore done
clear
B)
Trabaculae done
clear
C)
Obturator done
clear
D)
Translator done
clear
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question_answer6)
The diagram below is a longitudinal section of an ovule of an angiosperm
With which of the following structures do the contents of one pollen tube fuse with
A)
1 and 3 done
clear
B)
1 and 4 done
clear
C)
2 and 3 done
clear
D)
3 and 4 done
clear
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question_answer7)
At what stage of endosperm development, you will observe nuclear or cellular type of endosperm
A)
When divisions starts in embryo done
clear
B)
When embryo is heart-shaped done
clear
C)
Mature stage of endosperm done
clear
D)
Just after division of primary endosperm nucleus done
clear
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question_answer8)
Micropyle allows [CPMT 1978]
A)
Pollen tube to penetrate in the ovule at the time of fertilization done
clear
B)
Activity of germination of pollen grains done
clear
C)
A pore in pollen grain done
clear
D)
The growing up of pollen grain done
clear
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question_answer9)
Which of the following statement is correct for the pollen tube [NCERT 1980; CBSE PMT 1993]
A)
It shows chemotactic movement done
clear
B)
It shows only tip growth done
clear
C)
It is composed of three non-cellular zones done
clear
D)
It shows radial cytoplasmic streaming done
clear
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question_answer10)
Even after killing the generative cell with a laser beam, the pollen grain of a flowering plant germinates and produces normal pollen tube because [NCERT 1983; CBSE PMT 1989; JIPMER 1993]
A)
Laser beam stimulates pollen germination and pollen tube growth done
clear
B)
The laser beam does not damage the region from which pollen tube emerges done
clear
C)
The contents of killed generative cell permit germination and pollen tube growth done
clear
D)
The vegetative cell has not been damaged done
clear
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question_answer11)
After penetrating stigmatic and styler tissues, the pollen tube usually grow down towards the egg because [CPMT 1985]
A)
The egg cell attracts the pollen tube as they have dissimilar electric charge done
clear
B)
The filiform apparatus of synergids is believed to attract the pollen tube done
clear
C)
It has no other passage to follow done
clear
D)
It grows under control of nucleus done
clear
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question_answer12)
Double fertilization process means [CBSE PMT 1991; CPMT 1972, 73, 81, 84, 87, 94, 95; NCERT 1969, 71; MP PMT 1997; DPMT 1983; BHU 1976, 82, 91, 99]
A)
Fusion of one male gamete nucleus with egg nucleus while fusion of other male gamete nucleus with secondary nucleus done
clear
B)
Fusion of male gamete nucleus with secondary nucleus done
clear
C)
Fusion of two polar nuclei with each other done
clear
D)
Fusion of male gamete nucleus with egg nucleus done
clear
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question_answer13)
The endosperm found in angiospermic seed is different from that of gymnosperms in the sense that, in the former [Bihar 1991]
A)
It is formed before fertilization while in the latter it is formed after fertilization done
clear
B)
It is formed after fertilization while in the latter it is formed before fertilization done
clear
C)
It is cellular while in the latter it is nuclear done
clear
D)
It is nutritive while in the latter it is protective done
clear
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question_answer14)
Sperm cells of angiosperms differ from the rest of the plant groups like gymnosperms by [AFMC 1993]
A)
In angiosperms the sperm cells are non-motile whereas in the others they are flagellate done
clear
B)
In angiosperms the sperm cells are produced in the pollen grain whereas in the rest they are produced in the antheridium done
clear
C)
In angiosperms and gymnosperms the sperm cells are non-motile whereas in the rest they are flagellated done
clear
D)
None of the above done
clear
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question_answer15)
When the pollen grains are not transferred from anthers to the stigma in flower due to the barrier or fence, it is referred as or when some natural barrier exists between androecium and gynoecium to check self pollination, it is known as [AIIMS 1993]
A)
Heterostyly done
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B)
Herkogamy done
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C)
Dichogamy done
clear
D)
Cleistogamy done
clear
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question_answer16)
Which is the most logical sequence with reference to the life cycle of angiosperms [DPMT 1993]
A)
Germination, endosperm formation, seed dispersal, double fertilization done
clear
B)
Pollination, fertilization, seed formation, germination done
clear
C)
Cleavage, fertilization, grafting, fruit formation done
clear
D)
Maturation, mitosis, differentiation, fertilization done
clear
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question_answer17)
By tissue culture, indefinite number of plants from a small amount of parental tissue can be obtained. This technique is of great economic importance as [AIIMS 1994]
A)
New species can be generated done
clear
B)
Through somaclonal variation, a large number of variants can be isolated done
clear
C)
It is a useful method to multiply genetically uniform population of elite species done
clear
D)
Homozygous diploids can be obtained done
clear
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question_answer18)
Despite high level of heterozygosity, the progeny derived from seed of a cross pollinated plant was found to be completely uniform. One reason for this may the phenomenon of [BHU 1994]
A)
Parthenocarpy done
clear
B)
Apomixis done
clear
C)
Induced mutation done
clear
D)
Polyploidy done
clear
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question_answer19)
Which of the following four phases, in the post emergence life of an angiospermic plant, begins just after germination of seed and ends when the plant develops the capacity to reproduce [KCET 1999]
A)
Death done
clear
B)
Ageing done
clear
C)
Maturity done
clear
D)
Juvenility done
clear
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question_answer20)
For pollinated ovary which is correct [BHU 1999]
A)
Accessory cells are diploid done
clear
B)
Antipodal cells are haploid done
clear
C)
Egg cell is diploid done
clear
D)
Ovule cell is haploid done
clear
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question_answer21)
If the diploid number of an angiospermic plant is 24, the number of chromosomes in the pollen grain, endosperm and integument will be [CPMT 2000]
A)
12, 36, 12 done
clear
B)
12, 24, 36 done
clear
C)
12, 12, 36 done
clear
D)
12, 36, 24 done
clear
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question_answer22)
Secondary nucleus in the middle of an embryo sac of angiosperms is [BHU 1999; AIEEE 2003]
A)
Diploid done
clear
B)
Triploid done
clear
C)
Tetraploid done
clear
D)
Haploid done
clear
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question_answer23)
In angiosperms the pollen grain is normally pollinated at [AMU 2005]
A)
One cell stage done
clear
B)
Two celled stage done
clear
C)
Three celled stage done
clear
D)
Four celled stage done
clear
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