General Q&A for Class 12 · Page 70
5,215 free answers in General for Class 12 students, across CBSE, ICSE and State boards.
Question & Answer
Questions
- GeneralClass 12All
What are the causes and consequences of deforestation? Causes of Deforestation:
Human-made causes: Agricultural expansion and clearing land for farming Logging for timber, paper, and furniture industries Infrastructure development (roads, dams, urbanization) Mining operations Forest fires (often deliberately set) Natural causes: Wildfires triggered by lightning or extreme heat Severe droughts Pest infestations Natural disasters like floods
- GeneralClass 12All
In what way do some tribals depend on forests?
Tribal communities have deep, multifaceted relationships with forests that sustain their livelihoods and culture: Food and Nutrition: Gathering fruits, nuts, honey, mushrooms, and hunting for meat provides dietary diversity and nutrition. Medicine: Collecting medicinal plants and herbs for treating illnesses using traditional knowledge passed through generations. Shelter: Using bamboo, wood, and leaves to construct hom
- GeneralClass 12All
Flora and Fauna Classification Which of the following belongs to 'fauna' and which belongs to 'flora' of the Pachmarhi Biosphere Reserve: Sal, Arjun, Cheetal, Teak, Leopard, Fern, Blue Bull, Barking deer, Mango, Wolf?
Flora (Plant life): Sal (tree) Arjun (tree) Teak (tree) Fern (plant) Mango (tree) Fauna (Animal life): Cheetal (deer species) Leopard (big cat) Blue Bull (nilgai - largest Asian antelope) Barking deer (small deer species) Wolf (carnivorous mammal) Flora refers to all plant species in an ecosystem, including trees, shrub
- GeneralClass 12All
Conservation Strategies and Protected Areas What is the difference between afforestation and reforestation?
hough both involve planting trees, afforestation and reforestation have distinct meanings: Afforestation is planting trees in areas that have never been forested or have been treeless for a very long time. This creates entirely new forests in barren lands, grasslands, or deserts. For example, planting trees in arid regions or converting wasteland into forest. Reforestation is replanting trees in areas where forests previously existed but were
- GeneralClass 12All
What is the difference between a zoo and wildlife sanctuaries?
Artificial environments where animals are kept in enclosures for public viewing, education, and breeding programs Animals are confined to limited spaces and fed by caretakers Primarily located in urban areas for easy public access Focus on conservation through captive breeding and public awareness Animals cannot exhibit fully natural behaviors Wildlife Sanctuaries: Natural habitats where animals liv
- GeneralClass 12All
Deforestation and Environmental Impact How does the fertility of soil decrease due to deforestation?
Deforestation severely impacts soil fertility through multiple mechanisms. Trees and their root systems bind soil particles together, and when removed, the topsoil—which contains most nutrients and organic matter—becomes vulnerable to erosion by wind and water. Tree roots also help maintain soil structure, allowing water infiltration and preventing nutrient leaching. Without forest cover, rainfall directly strikes the ground, washing away fertile topsoil. Additionally, trees contr
- GeneralClass 12All
What is a wildlife sanctuary? Name any two wildlife sanctuaries in India. Where are these sanctuaries located?
A wildlife sanctuary is a protected area dedicated to conserving wildlife and their natural habitats, where hunting and poaching are prohibited. Unlike national parks, sanctuaries may allow some controlled human activities that don't harm wildlife. Two prominent wildlife sanctuaries in India are: Periyar Wildlife Sanctuary - Located in Kerala, this sanctuary is famous for its elephant and tiger populations, set around the scenic Periyar Lake.
- GeneralClass 12All
How does the fertility of soil decrease due to deforestation?
Deforestation severely impacts soil fertility through multiple mechanisms. Trees and their root systems bind soil particles together, and when removed, the topsoil—which contains most nutrients and organic matter—becomes vulnerable to erosion by wind and water. Tree roots also help maintain soil structure, allowing water infiltration and preventing nutrient leaching. Without forest cover, rainfall directly strikes the ground, washing away fertile topsoil. Additionally, trees contr
- GeneralClass 12All
With the help of the structure, describe the basic design of a Biosphere Reserve.
A Biosphere Reserve follows a zonation model with three distinct, concentric zones: Core Zone (Innermost area): Strictly protected natural area No human activity permitted except research with special permission Preserves pristine ecosystems and endangered species Legal protection under wildlife laws Buffer Zone (Middle ring): Surround
- GeneralClass 12All
What do you mean by the term conservation?
Conservation refers to the careful management and protection of natural resources, wildlife, and ecosystems to prevent their depletion or destruction. It involves sustainable practices that balance human needs with environmental preservation, ensuring that forests, water bodies, soil, plants, and animals are available for future generations. Conservation includes activities like protecting endangered species, maintaining biodiversity, preventing deforestation, and promoting sustainable use of
- GeneralClass 12All
Which biosphere reserve is located in Assam?
The Dibru-Saikhowa Biosphere Reserve is located in Assam, situated in the northeastern region of India. This reserve is known for its rich biodiversity, including rare and endangered species like the white-winged wood duck and hoolock gibbons. The biosphere reserve plays a crucial role in conserving the unique flora and fauna of the region while supporting sustainable development for local communities.
- GeneralClass 12All
What is the difference between a zoo and wildlife sanctuaries? Zoos:
Artificial environments where animals are kept in enclosures for public viewing, education, and breeding programs Animals are confined to limited spaces and fed by caretakers Primarily located in urban areas for easy public access Focus on conservation through captive breeding and public awareness Animals cannot exhibit fully natural behaviors Wildlife Sanctuaries: Natural habitats where animals liv
- GeneralClass 12All
How are deforestation and decreased rainfall related?
Deforestation and decreased rainfall are interconnected through the water cycle. Trees play a crucial role in maintaining regional rainfall patterns through transpiration—the process of releasing water vapor into the atmosphere through their leaves. This moisture contributes to cloud formation and precipitation. When forests are cleared, transpiration decreases dramatically, reducing atmospheric moisture and disrupting local weather patterns. Additionally, forests act as natural water r
- GeneralClass 12All
What is the name of microorganisms which reproduce only inside the living cells of other organisms?
Viruses are unique microorganisms that can only reproduce inside the living cells of other organisms. Unlike bacteria and other microbes, viruses are not considered fully alive because they cannot carry out life processes independently. They consist of genetic material (DNA or RNA) wrapped in a protein coat and lack the cellular machinery needed for reproduction. When a virus infects a host cell, it hijacks the cell's mechanisms to make copies of itself, often destroying the
- GeneralClass 12All
Name the instrument (or device) which is needed to see microorganisms.
A microscope is the essential instrument used to observe microorganisms, which are too small to be seen with the naked eye. The most commonly used type is the compound light microscope, which uses multiple lenses and light to magnify tiny organisms up to 1000-2000 times their actual size. For viewing extremely small microbes like viruses, scientists use electron microscopes that can magnify specimens up to millions of times. Anton van Leeuwen
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Name the microorganism which is used for the large-scale production of alcohol.
Yeast, specifically the species Saccharomyces cerevisiae, is the primary microorganism used for large-scale commercial alcohol production. This single-celled fungus ferments sugars from various sources (grains, fruits, sugarcane) into ethanol (alcohol) and carbon dioxide under anaerobic (oxygen-free) conditions. The brewing and distilling industries rely on different yeast strains optimized for producing beer, wine, whiskey, rum, vodka, and other alc
- GeneralClass 12All
Name two diseases caused by protozoans.
Malaria and Amoebic Dysentery are two common diseases caused by protozoans. Malaria, caused by Plasmodium species, is transmitted through mosquito bites and affects millions worldwide, causing fever, chills, and potentially fatal complications if untreated. Amoebic dysentery, caused by Entamoeba histolytica, spreads through contaminated food and water, leading to severe diarrhea, abdominal pain, and intestinal infections. Other notable proto
- GeneralClass 12All
What will you observe if you keep moist bread outside in the open for few days?
If you keep moist bread exposed in the open for several days, you'll observe cotton-like or powdery growth appearing on its surface, typically in white, green, blue, or black colors. This growth is fungus (mold), which develops from fungal spores present in the air that land on the bread and germinate in the moist, nutrient-rich environment. The bread provides food for the fungi, while moisture allows the spores to grow into thread-like structures called hyph
- GeneralClass 12All
Why is yeast used in the baking industry?
Yeast, particularly Saccharomyces cerevisiae (baker's yeast), is essential in baking because it produces carbon dioxide gas through fermentation, which makes dough rise and creates the light, fluffy texture we enjoy in bread, cakes, and pastries. When yeast is mixed with flour, water, and sugar, it ferments the sugars, releasing CO₂ bubbles that get trapped in the dough's gluten network, causing it to expand. This process also produces small amounts
- GeneralClass 12All
What is Crop Rotation?
Crop rotation is the systematic practice of growing different types of crops sequentially on the same land across different seasons or years in a planned, cyclical pattern. Rather than continuously cultivating the same crop, farmers alternate between crops with different nutrient requirements, growth patterns, and pest profiles. A typical rotation might involve growing wheat, then legumes (like chickpeas), followed by cotton, and then returning to wheat in a three-year cycle.