In the grassland, trees do not replace the grasses as a part of an ecological succession because of_____.

Improper handling and storage of cereal grains and oilseeds result in the production of toxins known as aflatoxins, which are not generally destroyed by the normal cooking process. Aflatoxins are produced by:  

Which of the following diseases can be transmitted from one person to another through tattooing?

$1$. Chikungunya

$2$. Hepatitis-B

$3$. HIV-AIDS

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With reference to the food chains in ecosystems, which of the following kinds of organism is/are known as decomposer organism/organisms?

1. Virus

2. Fungi       

3. Bacteria

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Which of the following statements is/are correct?

1. Viruses lack enzymes necessary for the generation of energy.

2. Viruses can be cultured in any synthetic medium.

3. Viruses are transmitted from one organism to another by biological vectors only.

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Which of the following leaf modifications occurs/occur in desert areas to inhibit water loss?

1. Hard and waxy leaves

2. Tiny leaves or no leaves

3. Thorns instead of leaves.

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