Tag: pre fertilization - plants
Questions Related to pre fertilization - plants
The apical growing region of pollen tube called
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Growing zone
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Cap block
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Non-vacuolate region
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Organelle region
Apical zone of pollen tube contains abundant vesicles but lacks cell organelles. It is hemisphere in shape and transparent in nature. This transparent apical growing region of pollen tube is called as cap block. It exists only until the tube is growing. It disappears as soon as the growth ceases.
The functional part of the pollen tube is separate from the rest by
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Vacuoles
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Callose plugs
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Septa
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Both B and C
Callose is a beta-1,3-glucan. It is the major component of the pollen tube cell wall. It is also deposited within the cytoplasm as distinct callose grains. This leads to the formation of callose plugs. Callose plugs separate the living, growing and functional part of the pollen tube in the tip from the remaining degenerating part.
Site of meiosis in angiosperms is
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Meristem
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Spore mother cell
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Roots
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Petals or pollens
Site of meiosis in Angiosperms is the spore mother cell.
In plants, meiosis can be observed in
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Root tip
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Leaf primordia
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Sporangia
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Spores
In plants, meiosis can be observed in sporangia. A microsporangium is the part of plant is suitable for the study of meiosis. A typical anther contains four microsporangia. The microsporangia form sacs or locules in the anther. The two separate locules on each side of an anther may fuse into a single locule. Each microsporangium is lined with a nutritive tissue layer called the tapetum and initially contains diploid pollen mother cells. These undergo meiosis to form haploid spores. The spores may remain attached to each other in a tetrad or separate after meiosis.
Which of the following is the site of meiosis in higher plants?
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Growth cells
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Root tip cell
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Stomatal cell
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Spore mother cell
The site of meiosis in higher plants is the spore mother cell. In land plants and some algae, there is an alternation of generations such that meiosis in the diploid sporophyte generation produces haploid spores. These spores multiply by mitosis, developing into the haploid gametophyte generation, which then gives rise to gametes directly. In both animals and plants, the final stage is for the gametes to fuse, restoring the original number of chromosomes.
In which of the following meiosis takes place?
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Pollen grains
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Pollen tube
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Pollen mother cells
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Generative cells
Meiosis occurs in microspores mother cells which are diploid cells; to produce microspores or pollen grains. Each microspore mother cell produces four microspores after a meiotic division.
Which part of plant is suitable for the study of meiosis?
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Root apex
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Ovary
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Anther
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Shoot apex
Anther is the part of plant is suitable for the study of meiosis. A typical anther contains four microsporangia. The microsporangia form sacs or locules in the anther. The two separate locules on each side of an anther may fuse into a single locule. Each microsporangium is lined with a nutritive tissue layer called as the tapetum and initially contains diploid pollen mother cells. These undergo meiosis to form haploid spores. The spores may remain attached to each other in a tetrad or separate after meiosis.
Meiosis is best observed in dividing.
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Cells of apical meristem
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Cells of lateral meristem
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Microspores and anther wall
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Microsporocytes
In tomato, meiosis occurs in
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Pollen sac and ovule
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Microspore and megaspore mother cells
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Both A and B
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Zygote
How many meiotic divisions are required to produce $1000$ pollen grains?
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$200$
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$250$
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$500$
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$1000$