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प्रश्न
A free-living nitrogen-fixing cyanobacterium which can also form a symbiotic association with the water fern Azolla
विकल्प
Nostoc
Anabaena
chlorella
Rhizobium
उत्तर
Anabaena
संबंधित प्रश्न
Read the given statements and select the correct option.
- Hydrophytes possess aerenchyma to support themselves in water.
- Seeds of Viscum are positively photoblastic as they germinate only in presence of light.
- Hygroscopic water is the only soil water available to roots of plants growing in soil as it is present inside the micropores.
- High temperature reduces use of water and solute absorption by roots.
Read the given statements and select the correct option.
- Loamy soil is best suited for plant growth as it contains a mixture of silt, sand, and clay.
- The process of humification is slow in the case of organic remains containing a large amount of lignin and cellulose.
- Capillary water is the only water available to plant roots as it is present inside the micropores.
- Leaves of shade plant have more total chlorophyll per reaction centre, low ratio of chl a and chl b are usually thinner leaves.
Read the given statements and select the correct option.
Statement A: Cattle do not graze on weeds of Calotropis.
Statement B: Calotropis have thorns and spines, as a defense against herbivores.
In soil water available for plants is
Ophrys an orchid resembling the female of an insect so as to able to get pollinated is due to phenomenon of
In a fresh water environment like pond, rooted autotrophs are
Sticky glands of Boerhaavia and Cleome support
Sandy soil is not suitable for cultivation. Explain why?
What is myrmecophily?
What is co-evolution?
Explain different types of hydrophytes with examples.
Describe the dispersal of fruit and seeds by animals.
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 |
What is the soil profile? Explain the characters of different soil horizons.
