Class 10 Biology
Exemplar Problems MCQ I
From the list given below pick the item that is not a natural resource
Answer: (c) Electricity
Explanation: Electricity is made by humans by harnessing certain natural resources. Hence, electricity; in its usable form; cannot be termed as a natural resource.
The most rapidly dwindling natural resource in the world is
Answer: (b) Forests
Explanation: Resources in other options are non-exhaustible in nature. However, forests are being cleared because of human activities.
The most appropriate definition of a natural resource is that it is a substance/commodity that is
- present only on land
- a gift of nature which is very useful to mankind
- a man-made substance placed in nature
- available only in the forest
Answer: (b) a gift of nature which is very useful to mankind
Explanation: Option ‘c’ can be easily ruled out because natural resources are not man-made. Option ‘a’ is ruled out because natural resources are present everywhere.
The main cause for abundant coliform bacteria in the river Ganga is
- disposal of unburnt corpses into water
- discharge of effluents from electroplating industries
- washing of clothes
- immersion of ashes
Answer: (a) Disposal of unburnt corpses into water
Explanation: Coliform bacteria mainly come from human excreta. They can be present in unburnt corpses. Waste from other options do not contain human excreta.
The pH of water sample collected from a river was found to be acidic in the range of 3.5 – 4.5. On the banks of the river were several factories that were discharging effluents into the river. The effluents of which one of the following factories is the most likely cause for lowering the pH of river water?
- Soap and detergent factory
- Lead battery manufacturing factory
- Plastic cup manufacturing factory
- Alcohol distillery
Answer: (d) Alcohol distillery
Explanation: Fermentation is the chemical procedure which is utilized in alcohol industry. We know that fermentation produces lactic acid and ethanol. Ethanol changes into ethanoic acid on oxidation. Hence, option ‘d’ is the correct answer.
The pH range most conducive for life of fresh water plants and animals is
- 6.5 – 7.5
- 2.0 – 3.5
- 3.5 – 5.0
- 9.0 – 10.5
Answer: (a) 6.5 – 7.5
Explanation: A neutral pH is most conducive for living beings in freshwater. The pH range in option ‘a’ is nearest to neutral.
The three R’s that will help us to conserve natural resources for long term use are
- recycle, regenerate, reuse
- reduce, regenerate, reuse
- reduce, reuse, redistribute
- reduce, recycle, reuse
Answer: (d) reduce, recycle, reuse
Given below are a few statements related to biodiversity. Pick those that correctly describe the concept of biodiversity
- Biodiversity refers to the different species of flora and fauna present in an area
- Biodiversity refers to only the flora of a given area
- Biodiversity is greater in a forest
- Biodiversity refers to the total number of individuals of a particular species living in an area
- (i) and (ii)
- (ii) and (iv)
- (i) and (iii)
- (ii) and (iii)
Answer: (c) (i) and (iii)
Explanation: Both flora and fauna are included in biodiversity. Biodiversity is in greater degree in a forest. Hence, options (ii) and (iv) are incorrect.
Among the statements given below select the ones that correctly describe the concept of sustainable development
- Planned growth with minimum damage to the environment
- Growth irrespective of the extent of damage caused to the environment
- Stopping all developmental work to conserve the environment
- Growth that is acceptable to all the stakeholders
- (i) and (iv)
- (ii) and (iii)
- (ii) and (iv)
- (iii) only
Answer: (a) (i) and (iv)
Explanation: Options ‘ii’ and ‘iii’ show highly contrasting situations. A balance of both is required. Economic growth is a necessity and so is minimizing the damage to the environment. Hence, options (ii) and (iii) are incorrect.
In our country, vast tracts of forests are cleared and a single species of plant is cultivated. This practice promotes
- biodiversity in the area
- monoculture in the area
- growth of natural forest
- preserves the natural ecosystem in the area
Answer: (b) monoculture in the area
Explanation: Growing a single species of plant or animal is called monoculture.
A successful forest conservation strategy should involve
- protection of animals at the highest trophic level
- protection of only consumers
- protection of only herbivores
- comprehensive programme to protect all the physical and biological components
Answer: (d) comprehensive programme to protect all the physical and biological components
Explanation: Protection of organisms at a single trophic level cannot maintain a balance in the ecosystem. Hence, other options are ruled out.
The important message conveyed by the ‘Chipko Movement’ is
- to involve the community in forest conservation efforts
- to ignore the community in forest conservation efforts
- to cut down forest trees for developmental activities
- government agencies have the unquestionable right to order destruction of trees in forests
Answer: (a) to involve the community in forest conservation efforts
Explanation: The Chipko Movement showed a bottom up approach. The whole idea of this movement was never imposed from the top leadership. This was the reason for the success of this movement.