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प्रश्न
Describe the structure of anatropus ovule with the help of a labelled diagram.
उत्तर
Structure of anatropous ovule:
- Anatropous ovule is the most common type of ovule in angiosperms.
It consists of the following parts: - Funiculus/Stalk/Funicle: Each ovule develops inside the ovary. Ovule is attached to the placenta by a small stalk called funiculus.
- Hilum: The point of attachment of the funiculus to the main body of the ovule is known as the hilum.
- Nucellus: The ovule consists of central parenchymatous tissue called nucellus.
- Integuments: Nucellus is usually surrounded by two protective coverings called integuments viz. outer and inner integument.
- Micropyle: A narrow opening at the apex of the ovule is called the micropyle. Its anatropous ovule, micropyle is directed downwards and is present adjacent to the funiculus (funicle).
- Chalaza: Chalaza is the base of the ovule directly opposite to the micropyle.
- Embryo sac: The embryo sac (female gametophyte) is an oval multicellular structure embedded in the nucellus.
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संबंधित प्रश्न
Describe the structure of pollen grain.
Describe the internal structure of anther (diagram is not expected).
Describe the development of female gametophyte of angiosperms with the help of diagram.
Generally, ____________ megaspore/s takes part in the development of female gametophyte.
The diagram given below represents an anatropous ovule. Identify labels 'X' and 'Y' in.
From the following identify the pair of plant parts which is haploid.
Match Column - I with Column - II and select the correct option.
| Column - I | Column - II | ||
| (a) | Sunflower | (i) | Protogyny |
| (b) | Castor | (ii) | Self-incompatibility |
| (c) | Michelia | (iii) | Protandry |
| (d) | Orchid | (iv) | Unisexuality |
Match the parts of the ovule given in column I with the parts of the seed given in column II:
| Column I | Column II |
| (a) egg | (1) testa |
| (b) nucellus | (2) tegmen |
| (c) outer integument | (3) perisperm |
| (d) inner integument | (4) embryo |
Outer integument and inner integument of an ovule change into ______.
