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प्रश्न
Why do moss plants produce very large number of male gametes? Provide one reason. What are these gametes called?
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उत्तर १
Moss plants produce a large number of male gametes to increase the chances of fertilisation, as the eggs are located in the archegonium and the male gametes have to swim in water to reach the eggs for fertilisation to occur. The male gametes are called antherozoids.
उत्तर २
Moss plants produce a very large number of male gametes because the male gametes need to move through a moist environment to reach the egg for fertilization. Many male gametes fail to reach the egg, so producing them in large numbers compensates for this loss. These male gametes are called antherozoids.
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संबंधित प्रश्न
Mention two strategies that evolved to prevent self-pollination in flowers.
Complete the following chart and rewrite.
| Sr.No. | Agencies | type of pollination |
| 1 | Water | .................... |
| 2 | ........................... | Entomophily |
| 3 | Bat | .................... |
| 4 | ....................... | Ornithophily |
(Or)
Explain outbreeding devices in angiospermic plants.
Which one of the following is one of the characteristics of self-pollinated flowers?
Describe the advantages and disadvantages of cross-pollination to the plant.
In bisexual flowers, maturation of gynoecium before androecium is known as ______.
Differentiate between geitonogamy and xenogamy (allogamy).
For which of the following attractants and rewards are required?
Which of the following pair has haploid structures?
Which of the following is not a water pollinated plant?
Triple fusion in Capsella bursa pastoris is fusion of male gamete with ______.
Which of these is a condition that makes flowers invariably autogamous?
The flower which possesses both androecium and gynoecium is called perfect or ______.
Which of the following plant contain unisexual flower?
The flower which does not open at all are called ______.
Match the Column I with Column II.
| Column I | Column II |
| A. Pea | (i) Xenogamy |
| B. Jawar | (ii) Epihydrophily |
| C. Maize | (iii) Anemophily |
| D. Vallis | (iv) Bisexual |
| E. Cannabis | (v) Geitonogamy |
Briefly discuss any two methods by which plants avoid self-pollination.
Name the pollinating agent of a flowering plant with large and coloured flowers with sticky stigma. State one characteristic feature of the pollen grains produced in such flowers.
Comparatively a large amount of pollen grains are wasted during ______.
Identify the set of correct statements:
- The flowers of Vallisneria are colourful and produce nectar.
- The flowers of waterlily are not pollinated by water.
- In most of water-pollinated species, the pollen grains are protected from wetting.
- Pollen grains of some hydrophytes are long and ribbon like.
- In some hydrophytes, the pollen grains are carried passively inside water.
Choose the correct answer from the options given below:
