Free Man and His Environment MCQs with Answers

221. Which endangered animal is the source of the world's finest, lightest, warmest and most expensive wool - the shahtoosh?

• A. Nilgai
• B. Cheetal
• C. Kashmiri goat
• D. Chiru

Explanation: The source of the world's finest, lightest, warmest, and most expensive wool known as "shahtoosh" is the Tibetan antelope, also known as the chiru (Pantholops hodgsonii). Shahtoosh is made from the downy undercoat of the Tibetan antelope, which is native to the Tibetan Plateau and surrounding regions in Central Asia. The production of shahtoosh wool is illegal and highly unethical due to the endangered status of the Tibetan antelope. The chiru is protected by international and national laws, and trade in shahtoosh products is banned to prevent the poaching and endangerment of these animals. The demand for shahtoosh has contributed to the decline of chiru populations, and conservation efforts are in place to protect this endangered species.

222. Wildlife is continuously decreasing. What is the main reason of this?

• A. Predation
• B. Cutting down of forest
• C. Destruction of habitat
• D. Hunting

Explanation: Wildlife refers to all living organisms (terrestrial, aquatic and aerial) living in all possible natural habitats of their own, other than the cultivated plants and domesticated animals. Thus "wildlife" does not exist only in jungles and are hunted down but wild life includes even the migrating birds, turtles, coral reefs, microorganisms, insects, fishes, etc. Several hundred organisms are endangered or on the verge of extinction. The reasons are deforestation, pollution, killing, over exploitation etc. The destruction and fragmentation of natural habitats due to urbanization, agriculture, deforestation, and infrastructure development are major factors affecting wildlife. As humans expand their activities, they encroach on and alter the natural environments that wildlife depend on.

223. The indri-­indri lemur is found in:

• A. Madagascar
• B. Mauritius
• C. India
• D. Sri Lanka

Explanation: The indri (Indri indri) is a large, arboreal lemur species found in the eastern rainforests of Madagascar. It is native to the island of Madagascar and is known for its distinctive appearance, characterized by black and white fur and a unique vocalization. The indri is considered one of the largest living lemurs and is known for its leaping locomotion in the trees. It is endemic to Madagascar and is primarily found in the eastern rainforest regions of the island. Due to habitat loss and other threats, the indri is listed as an endangered species, and conservation efforts are in place to protect its habitat and population.

224. The viable material of an endangered species can be preserved by:

• A. Gene banks
• B. Gene libraries
• C. Herbariums
• D. Gene pools

Explanation: The viable material of an endangered species can be preserved by gene banks. A gene bank is an institute that maintains stocks of viable seeds (seed banks), live growing plants (orchards), tissue cultures and frozen germplasm with a whole range of genetic variability. Gene banks are often used in conjunction with other conservation strategies to ensure the resilience and persistence of endangered species.

225. What is the major cause of diminishing wildlife number?

• A. Felling of trees
• B. Paucity of drinking water
• C. Cannibalism
• D. Habitat destruction

Explanation: Wildlife refers to all living organisms (terrestrial, aquatic and aerial) living in all possible natural habitats of their own, other than the cultivated plants and domesticated animals. Thus "wildlife" does not exist only in jungles and are hunted down but wildlife includes even the migrating birds, turtles, coral reefs, microorganisms, insects, fishes, etc. Several hundred organisms are endangered or on the verge of extinction. The reasons are deforestation, pollution, killing, over exploitation etc. The destruction and fragmentation of natural habitats due to urbanization, agriculture, deforestation, and infrastructure development are major factors affecting wildlife. As humans expand their activities, they encroach on and alter the natural environments that wildlife depend on.

226. The most important human activity leading to the extinction of wildlife is

• A. Pollution of air and water.
• B. Hunting for valuable wildlife products.
• C. Introduction of alien species.
• D. Alteration and destruction of the natural habitats.

Explanation: Wildlife refers to all living organisms (terrestrial, aquatic and aerial) living in all possible natural habitats of their own, other than the cultivated plants and domesticated animals. Thus "wildlife" does not exist only in jungles but it includes even the migrating birds, turtles, coral reefs, microorganisms, insects, fishes, etc. The alteration and destruction of natural habitats, often as a result of human activities, are significant drivers of environmental degradation and biodiversity loss. These changes to natural landscapes have a range of negative consequences for ecosystems, wildlife, and the planet as a whole. When natural habitats are altered or destroyed, the plant and animal species that depend on them can lose their homes and food sources. This can lead to a decline in biodiversity, with some species facing extinction.

227. Which one of the following statements is not valid for aerosols?

• A. They alter rainfall and monsoon patterns.
• B. They cause increased agricultural productivity.
• C. They have negative impact on agricultural land.
• D. They are harmful to human health.

Explanation: Aerosols are harmful environmental pollutants which have negative effects on agriculture. Aerosols can have several negative impacts on agricultural lands, affecting crop health, soil quality, and overall agricultural productivity. Aerosols, particularly those containing pollutants or toxic substances, can settle on crop surfaces. When aerosols are deposited on leaves or fruits, they can cause physical damage, reduce photosynthesis, and inhibit gas exchange, ultimately affecting crop yields and quality.

228. Biochemical Oxygen Demand (BOD) may not be a good index for pollution for water bodies receiving effluents from:

• A. Domestic sewage
• B. Dairy industry
• C. Petroleum industry
• D. Sugar industry

Explanation: Biochemical Oxygen Demand (BOD) is a commonly used water quality parameter that measures the amount of dissolved oxygen consumed by microorganisms while they decompose organic matter in water. Petroleum is not degraded by decomposer microbes.

229. A lake which is rich in organic waste may result in:

• A. Increased population of aquatic organisms due to minerals.
• B. Drying of the lake due to algal bloom.
• C. Increased population of fish due to lots of nutrients.
• D. Mortality of fish due to lack of oxygen.

Explanation: High amount of organic waste in a lake will trigger and activate decomposer microbes which will decompose organic waste. Biochemical Oxygen Demand (BOD) of this lake will shoot up and decomposers will utilize most of the dissolved oxygen present in lake. Consequently, the level of dissolved oxygen will go down to alarming extent. Aquatic animals like fish which totally depend on the oxygen dissolved in water will ultimately die.

230. The highest DDT concentration in the aquatic food chain will be found in a:

• A. Phytoplankton
• B. Seagull
• C. Crab
• D. Eel

Explanation: DDT is non-­biodegradable and is not metabolized within the body of an organism; rather it accumulates in the fat tissues therefore its concentration goes on increasing from one trophic level to another of a food chain. The highest amount is present in the top consumer i.e., it shows biomagnification. In an aquatic food chain, the seagull is the top carnivore, therefore, will possess the highest concentration of DDT.