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प्रश्न
What is pollination?
What is meant by pollination?
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उत्तर
Pollination is the transfer of pollen grains from the male part of a flower, the anther, to the female part, the stigma. This process is crucial for fertilization, leading to the development of seeds and fruits and ensuring the plant species survival.
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संबंधित प्रश्न
Match the following:
| Column A | Column B |
| (i) Stigma | (a) Neuron |
| (ii) Pepsin | (b) Carpel |
| (iii) Dendrites | (c) Protein |
| (d) Stamen |
Name the parts A, B and C shown in the diagram and write their functions.
Name the parts A, B and C shown in the following diagram and state one function of each.
A flower may have either male or female reproductive parts. Such a flower is called ______.
Sketch the reproductive parts of a flower.
Where are the pollen grains produced?
Fill in the following blank with suitable word :
Ovules contain ......... gametes of a plant.
Explain the terms 'cross-pollination'?
How is the process of pollination different from fertilization?
What is seed? What are the parts of a seed? Explain with the help of a labelled diagram.
Name the part of a seed which grows into root.
Name the part of a seed which grows into shoot.
What is meant by 'unisexual flowers' and 'bisexual flowers'? Give two examples of each.
(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
One of the following occurs in the reproductive system of flowering plants as well as that of humans. This is :
(a) vas deferens
(b) anther
(c) ovary
(d) style
The correct sequence of reproductive stages occurring in flowering plants is ______
The part of a seed which grows and develops into root on germination is :
(a) cotyledon
(b) plumule
(c) follicle
(d) radicle
The flask-shaped organ A at the centre of a flower is surrounded by a number of little stalks B having swollen tops which lie just inside the ring of petals.
(a) Name A. What are the various parts of A?
(b) Which part of A contains gametes?
(c) Name B. What is the swollen top of B known as?
(d) What does the swollen top of b contain?
(e) Out of A and B, which one is (i) male part, and (ii) female part of the flower?
In what ways is fertilisation in a plant different from fertilisation in a human?
Fill in the blank by selecting suitable word:
A flower bearing only male or female parts is known as __________ flower.
State whether the following statement is true (T) or false (F):
Flowers which possess stamens and carpel are called unisexual.
Mention the function of Stigma.
What part is played by stamens and carpels in reproduction?
Write one main difference between asexual and sexual mode of reproduction. Which species is likely to have comparatively better chances of survival – the one reproducing asexually or the one reproducing sexually? Give reason to justify your answer.
(a) Identify A, B and C in the given diagram and write their functions.
(b) Mention the role of gamete and zygote in sexually reproducing organisms.
Distinguish between unisexual and bisexual flowers giving one example of each. Draw a diagram showing process of germination of pollen grains on stigma and label the following parts:
(a) Female germ cell
(b) Male germ cell
(c) Ovary
What is phototropism?
Identify the odd. Stigma, Style, Pollen, Ovary.
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?
Find the odd one out:
Calyx : Sepals : : Corolla : ________________
Accessory whorls : Calyx and corolla : : essential whorls : ______________
Write the functions of sepals
Distinguish between self-pollination and cross-pollination.
Where does the endothecium layer of anther lobes is present?
How many middle layers are generally present in the wall of the anther lobes?
Identify the female gametophyte in angiosperms.
What would be the number of chromosomes of the aleurone cells of a plant with 42 chromosomes in its roots tip cells?
Sperm and egg nuclei fuse due to ______.
Which among the following statements are true for unisexual flowers?
- They possess both stamen and pistil
- They possess either stamen or pistil
- They exhibit cross pollination
- Unisexual flowers possessing only stamens cannot produce fruits
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?
Double fertilization is exhibited by ______
In a plant flower the female whorl is ______.
What is the structural unit of sexual reproduction in plant?
