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प्रश्न
How does an Amoeba reproduce? Describe the process of reproduction in Amoeba with the help of labelled diagrams of different stages in its reproduction process.
उत्तर
The cell of an Amoeba after attaining its maximum size starts dividing. The nucleus of the cell divides first, followed by the cytoplasm. Thus, a single cell divides into two identical cells.
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संबंधित प्रश्न
On cutting the body of an organism into many pieces it was observed that many of these pieces developed as new individuals. Name the process and list two organisms in which this process may be observed. Draw a schematic diagram to illustrate the changes that are likely to be observed during the development of new individuals in any one of the organisms named.
A student in viewing under a microscope a permanent slide showing various stages of asexual reproduction by budding in yeast. Draw diagrams of what he observes (in proper sequence)
Fill in the following blank with suitable word :
Rose plants and sugar cane crop are usually grown by the ........... method.
Explain why, more complex multicellular organisms cannot give rise to new organisms through regeneration.
How can you grow money plant by vegetative propagation?
The micro-organism which reproduces by multiple fission is the one which causes the disease known as :
(a) Kala-azar
(b) marasmus
(c) malaria
(d) amoebiasis
There are four tiny organisms A, B, C and D. The organism A is a parasitic protozoan which causes a disease known as kala-azar. The organism B is a microscopic single-celled animal which causes malaria disease in human beings. The organism C is a unicellular animal which can change its body shape according to need, it has no fixed shape. The organism D is also a unicellular animal which is slipper-shaped having a large number of tiny hair all around its body.
(a) Name the organisms A, B, C and D
(b) Name one characteristic body feature of organism A.
(c) Name the insect which carries organism B and transmits it from one person to another.
(d) What name is given to the asexual method of reproduction of (i) organism A, and (ii) organism B?
(e) Where do organisms C and D live?
The stem of a fruit tree X fixed in soil is cut in a slanting way. The upper part of stem of another fruit tree Y of different variety of same species is also cut in a slanting way. The cut stem of tree Y, without roots but having some leaves, is placed over the rooted cut stem of tree X in such a way that their cut surfaces fit together properly. While joining the two cut stems, care is taken to make sure that the layer Z of one cut stem is in contact with layer Z of the other cut stem. The joint of cut stem is bound tightly with a piece of cloth and covered properly with polythene. Soon the cut heals and the two stems grow together and become one fruit tree producing leaves, flowers and fruits.
(a) What is the name of this method of producing plants or trees?
(b) What name is given to the cut stem of tree X having roots?
(c) What name is given to the cut stem of tree Y which has no roots but has some leaves?
(d) Name the layer Z.
(e) Why should the layer Z of one cut stem be in contact with the layer Z of the other cut stem?
(f) Name any four fruit trees which are usually bred by this technique.
(g) State any one advantage of producing fruit trees by this technique.
Asexual reproduction in yeast is ______.
Name the asexual reproductive structure of Chlamydomonas.