1. Preventive measures and biological control methods should be preferred for protecting crops because excessive use of chemicals leads to environmental problems. These chemicals are also poisonous for plants and animals. Preventive measures include proper soil and seed preparation, timely sowing of seRead more

    Preventive measures and biological control methods should be preferred for protecting crops because excessive use of chemicals leads to environmental problems. These chemicals are also poisonous for plants and animals. Preventive measures include proper soil and seed preparation, timely sowing of seeds, inter cropping and mixed cropping, usage of resistant varieties of crops, etc. On the other hand, biological control methods include the usage of bio-pesticides that are less toxic for the environment. An example of bio-pesticides is Bacillus thuringenes, which is an insect pathogen that kills a wide range of insect larvae. Therefore, both preventive measures and biological control methods are considered eco-friendly methods of crop protection.

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  2. The desirable agronomic characteristics for crop improvements are: (i) Tallness and profuse branching in any fodder crop. (ii) Dwarfness in cereals. These desirable agronomic characteristic help in increasing crop productivity. For more answers visit to website: https://www.tiwariacademy.com/ncert-sRead more

    The desirable agronomic characteristics for crop improvements are:
    (i) Tallness and profuse branching in any fodder crop.
    (ii) Dwarfness in cereals. These desirable agronomic characteristic help in increasing crop productivity.

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  3. (i) Cereals provide us with carbohydrates. Also, they are a rich source of energy. (ii) Pulses give us proteins. (iii) Fruits and vegetables are a rich source of vitamins and minerals. A small amount of proteins, carbohydrates, and fats are also present in them. For more answers visit to website: htRead more

    (i) Cereals provide us with carbohydrates. Also, they are a rich source of energy.
    (ii) Pulses give us proteins.
    (iii) Fruits and vegetables are a rich source of vitamins and minerals. A small amount of proteins, carbohydrates, and fats are also present in them.

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  4. The major divisions of Plantae and the basis for these divisions are as follows: • Thallophyta: Simple body design; with no differentiation into root, stem and leaves. • Bryophyta: Body is differentiated into stem and leaf-like structures. Vascular system is absent. • Pteridophyta: Body is differentRead more

    The major divisions of Plantae and the basis for these divisions are as follows:
    • Thallophyta: Simple body design; with no differentiation into root, stem and leaves.
    • Bryophyta: Body is differentiated into stem and leaf-like structures. Vascular system is
    absent.
    • Pteridophyta: Body is differentiated into root, stem and leaves. Vascular system is present.

    Reproductive organs are inconspicuous. Seeds are not produced.

    • Gymnosperms: Seeds are naked.
    • Angiosperms: Seeds are covered.

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  5. Parenchyma is a simple permanent tissue of angiospermic plants. It is present in cortex and pith of stem and roots. It is also present in mesophyll of leaves. When it contains chlorophyll, it is called Chlorenchyma, found in green leaves. For more answers visit to website: https://www.tiwariacademy.Read more

    Parenchyma is a simple permanent tissue of angiospermic plants. It is present in cortex and pith of stem and roots. It is also present in mesophyll of leaves. When it contains chlorophyll, it is called Chlorenchyma, found in green leaves.

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