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प्रश्न
Triple fusion involves ______.
पर्याय
Fusion of male gamete with female gamete
Fusion of tube nucleus with generative nucleus
Fusion of two polar nuclei
Fusion of second male gamete with two polar nuclei
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उत्तर
Triple fusion involves fusion of second male gamete with two polar nuclei.
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संबंधित प्रश्न
A student was asked to observe and identify the various parts of an embryo of a red kidney bean seed. He identified the parts and listed them as under:
I. Tegmen
II. Testa
III. Cotyledon
IV. Radicle
V. Plumule
The correctly identified parts among these are
(A) I, II and III
(B) II, III and IV
(C) III, IV and V
(D) I, III, IV and V
A student identified the various parts of an embryo of a gram seed and listed them as given below :
(I) Testa
(II) Plumule
(III) Radicle
(IV) Cotyledon
(V) Tegmen
Out of these the actual parts of the embryo are :
(A) I, II, III
(B) II, III, IV
(C) III, IV, V
(D) II, IV, V
You are asked by your teacher to study the different parts of an embryo of a gram seed. Given below are the steps to be followed for the experiment:
I. Soak the gram seeds in plain water and keep them overnight.
II. Cut open a soaked seed and observe its different parts.
III. Take some dry gram seeds in a petri dish.
IV. Drain the excess water.
V. Cover the soaked seeds with a wet cotton cloth and leave them for a day.
The correct sequence of these steps is :
(A) III, I, V, IV, II
(B) III, I, II, IV, V
(C) III, IV, V, I, II
(D) III, I, IV, V, II
How does the process of fertilisation take place in flowers?
The process of fusion of the male and female gametes is called ______.
Mature ovary forms the ______.
Name the male part of the flower.
Where are the pollen grains produced?
Where is the female gamete formed in flowering plants?
Fill in the following blank with suitable word :
The female organ of reproduction in the flower is the...........
Fill in the following blank with suitable word :
The male organ of reproduction in the flower is the.......... .
Draw a neat sketch of the carpel of a flower. Mark in it stigma, style and ovary.
Describe the process of fertilisation in a flower with the help of labelled diagrams.
(a) Draw a neat diagram of a flower showing its various parts. In this diagram mark stem, receptacle, sepals, petals, stamen and carpel.
(b) What name is given to (i) all the petals of a flower, and (ii) all the sepals of a flower?
(c) What are (i) stamen, and (ii) carpel, in a flower?
(d) What is the other name of carpel of a flower?
(e) What is the name of yellow powdery substance present in the anther of a flower?
The length of pollen tube depends on the distance between :
(a) pollen grain and upper surface of stigma
(b) pollen grain on upper surface of stigma and ovule
(c) pollen grain in anther and upper surface of stigma
(d) upper surface of stigma and lower part of style
When an insect sits on the flower of a plant then some particles A present in the top of little stalks in the flower attach to its body hair. When this insect now sits on the flower of another similar plant, then particles A attached to the hair of insect are put on the top of a flask-shaped organ at the centre of flower. The particle A grows a long tube b from the top of flask-shaped organ through which C moves down and reaches the bottom part of flask-shaped organ. Here C fuses with the nucleus of d contained in structure E. the fusion of C and D forms a new cell f which grows and develops into a seed of the plant.
(a) What are particles A? What is the process of transferring A from one flower to another flower of similar plant by the insect known as?
(b) What is the name of tube B?
(c) What is C which moves down through the tube B?
(d) Name D and E.
(e) What is F?
In what ways is fertilisation in a plant similar to fertilisation in a human?
What part is played by stamens and carpels in reproduction?
“Cell division is a type of reproduction in unicellular organism.” Justify.
What is phototropism?
Mention pollination types.
What is meant by pollination?
Find an odd one out.
Define.
Inflorescence
Give scientific reason.
Flower is a structural unit of sexual reproduction in plants.
Draw a neat and labelled diagram.
Double fertilization in angiosperms
Write the events involved in the sexual reproduction of a flowering plant.
a. Discuss the first event and write the types.
b. Mention the advantages and the disadvantages of that event.
Where does the endothecium layer of anther lobes is present?
The ovule of an angiosperm is technically equivalent to ______
Variations occur as a result of ______
State the number of sets of chromosomes present in a zygote.
Double fertilization is exhibited by ______
Sketch and label the essential and accessory whorls of flower.
The figure below shows the concept of double fertilization. Complete the flow chart showing the progress at each step:
In flowering plants, the pollen grains are transferred to stigma by pollination but the female germ cells are present in the ovary.
Explain with the help of a labelled diagram (only concerned parts), how the male germ cell reaches the ovary.
The pollen tube usually enters the embryo sac ______.
