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प्रश्न
Describe the dispersal of fruit and seeds by animals.
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उत्तर
Birds and mammals, including human beings, play an efficient and important role in the dispersal of fruit and seeds. They have the following devices.
- Hooked fruit: The surface of the fruit or seeds have hooks (Xanthium), barbs (Andropogon), spines (Aristida) by means of which they adhere to the body of animals or clothes of human beings and get dispersed.
- Sticky fruits and seeds:
- Some fruits have sticky glandular hairs by which they adhere to the fur of grazing animals. Example: Boerhaavia and Cleome.
- Some fruits have a viscid layer that adheres to the beak of the bird which eats them and when they rub them onto the branch of the tree, they disperse and germinate.
Example: Cordia and Alangium.
- Fleshy fruits: Some fleshy fruits with conspicuous colours are dispersed by human beings to distant places after consumption.
संबंधित प्रश्न
Read the given statements and select the correct option.
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Statement B: Calotropis have thorns and spines, as a defense against herbivores.
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The plant of this group are adapted to live partly in water and partly above substratum and free from water
A free-living nitrogen-fixing cyanobacterium which can also form a symbiotic association with the water fern Azolla
Strong, sharp spines that get attached to animal’s feet are found in the fruits of
Sticky glands of Boerhaavia and Cleome support
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What is thermal stratification? Mention their types.
What is myrmecophily?
What is a seed ball?
Explain different types of hydrophytes with examples.
What are the advantages of seed dispersal?
Read the following statements and fill up the blanks with the correct option.
- Total soil water content in soil is called ______
- Soil water not available to plants is called ______
- Soil water available to plants is called ______
Column I represent the size of the soil particles and Column II represents the type of soil components. Which of the following is the correct match for the Column I and Column IL
| Column - I | Column - II | ||
| I) | 0.2 to 2.00 mm | i) | Slit soil |
| II) | Less than 0.002 mm | ii) | Clayey soil |
| III) | 0.002 to 0.02 mm | iii) | Sandy soil |
| IV) | 0.002 to 0.2 mm | iv) | Loamy soil |
