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प्रश्न
What is pollination? Mention its types.
उत्तर
- The process of transfer of pollen grains from another to stigma is called pollination.
- There are two types: Self-pollination and cross-pollination.
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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
Sketch the reproductive parts of a flower.
The process of fusion of the male and female gametes is called ______.
Name the part made up of the stigma, style and ovary.
Fill in the following blank with suitable word :
The female organ of reproduction in the flower is the...........
What changes take place in the flower after fertilisation which lead to the formation of seeds and fruit?
(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
Which among the following statements are true for unisexual flowers?
(i) They possess both stamen and pistil
(ii) They possess either stamen or pistil
(iii) They exhibit cross pollination
(iv) Unisexual flower possessing only stamens cannot produce fruits
(a) (i) and (iv)
(b) (ii), (iii) and (iv)
(c) (ii) and (iii)
(d) (i), (iii) and (iv)
Which of the following statements are true for sexual reproduction in flowering plants?
(i) it requires two types of gametes
(ii) fertilisation is a compulsory event
(iii) it always results in the formation of zygote
(iv) offsprings formed are clones
(a) (i) and (iv)
(b) (i), (ii) and (iv)
(c) (i), (ii) and (iii)
(d) (ii), (iii) and (iv)
In a bisexual flower, inspite of the young stamens being removed artificially, the flower produces fruit. Explain.
Fill in the blanks:
A stamen consists of ______ and ________.
Mention the function of Anther.
What are the male and female gametes in a flowering plant?
The students of a class were asked by the teacher to study the different parts of an embryo of an angiosperm. Given below are the essential steps for the experiment :
A. Soak the seeds in plain water and keep them overnight.
B. Cut open the soaked seed and observe its different parts.
C. Take some healthy seeds in a petri-dish.
D. Drain the excess water, cover the seeds with a wet cotton cloth and leave them as it is for a day.
The correct sequence of these steps is
(a) C, A, D, B
(b) C, D, A, B
(c) A, C, D, B
(d) A, C, B, D
Draw a diagram of the longitudinal section of a flower exhibiting germination of pollen on stigma and label (i) ovary, (ii) male germ-cell, (iii) female germ-cell and (iv) ovule on it.
Explain the process of fertilisation in flowers.
“Cell division is a type of reproduction in unicellular organism.” Justify.
Draw a diagram of a pistil showing pollen tube growth into the ovule and label the following:
Pollen grain, male gamete, female gamete, ovary.
Sketch the labeled diagram:
Flower with its sexual reproductive organs
Fill in the blanks and rewrite the completed statements:
Lymph flows in _______________ direction.
Draw a diagram of the longitudinal section of a flower and label the following parts.
What is meant by pollination?
Pollen grains are formed by _________ division in locules of anthers.
__________ is present in unisexual flower.
Flowers showing ornithophily show few characteristic like ______.
Length of pollen tube depends on the distance between ______
Which among the following statements are true for sexual reproduction in flowering plants?
- It requires two types of gametes
- Fertilisation is a compulsory event
- It always results in formation of zygote
- Offspring formed are clones
In a bisexual flower inspite of the young stamens being removed artificially, the flower produces fruit. Provide a suitable explanation for the above situation.
Give reason for the following:
Fertilization cannot take place in flowers if pollination does not occur.
Where is the zygote located in the flower after fertilization?
Draw the diagram of a flower and label the four whorls. Write the names of gamete producing organs in the flower.
Trace the path a male gamete takes to fertilise a female gamete after being released from the penis.
Give any two examples of agents of pollination.
In a plant flower the female whorl is ______.
What are the agents for pollination?
The figure below shows the concept of double fertilization. Complete the flow chart showing the progress at each step:
Name the reproductive parts of an angiosperm. Where are these parts located? Explain the structure of its male reproductive part.
Type of sexual reproduction is ______.
