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प्रश्न
Describe the structure of its microsporangium.
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उत्तर
A microsporangium is a cylindrical sac which appears circular in the transverse section. It contains the following parts:
(1) Outer wall
(2) Central homogeneous sporogenous tissue
(3) Epidermis
(4) Endothecium
(5) 1–3 middle layers and tapetum
The outer three layers perform the function of protection in the younger anther andthe mechanism of dehiscence in the ripe anther.The endothecial cells develop fibrous thickening of α-cellulose on the inner and radial walls and die. The innermost layer is called the tapetum. It nourishes the developing pollen grain.
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संबंधित प्रश्न
A flower of tomato plant following the process of sexual reproduction produces 240 viable seeds.
Answer the following questions giving reasons :
(a) What is the minimum number of pollen grains that must have been involved in the pollination of its pistil?
(b) What would have been the minimum number of ovules present in the ovary?
(c) How many megaspore mother cells were involved?
(d) What is the minimum number of microspore mother cells involved in the above case?
(e) How many male gametes were involved in this case?
The transfer of pollen grains from the anther to the stigma of the same or of another flower of the same kind is known as ______.
Write two ways in which pollination may occur in plants.
Fill in the blanks with suitable words.
Different timings for the maturation of gynoecium and androecium is called ________.
Give one word/term for the following:
When stigma and anthers do not grow up to the same height, which favors only cross-pollination.
Give one word/term for the following:
Pollination of flowers by birds.
Give an account of any two biotic agents for pollination along with their adaptations.
Both chasmogamous and cleistogamous flowers are present in ______.
Choose the correct statement from the following:
What is hypohydrophily?
