NCERT Class-9 Science Solutions: Chapter 14-Natural Resources Part 4

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Question 22:

Biotic component of biosphere is not constituted by

  1. Producers

  2. Consumers

  3. Decomposer

  4. Air

Answer: D

Image biotic component of biosphere

Image Biotic Component of Biosphere

Image biotic component of biosphere

Question 23:

An increase in carbon dioxide content in the atmosphere would not cause

  1. More heat to be retained by the environment

  2. Increase in photosynthesis in plants

  3. Global warming

  4. Abundance of desert plants

Answer: D

Image of increase In photosynthesis in plants

Image of Increase in Photosynthesis in Plants

Image of increase In photosynthesis in plants

Question 24:

Oxygen is returned to the atmosphere mainly by

  1. Burning of fossil fuel

  2. Respiration

  3. Photosynthesis

  4. Fungi

Answer: C

Image the oxygen cycle

Image the Oxygen Cycle

Image the oxygen cycle

Question 25:

Low visibility during cold weather is due to

  1. Formation of fossil fuel

  2. Unburnt carbon particles or hydrocarbons suspended in air

  3. Lack of adequate power supply

  4. None of these

Answer: B

Image hydrocarbons suspended in air

Image Hydrocarbons Suspended in Air

Image hydrocarbons suspended in air

Question 26:

Growth of Lichens on barren rocks is followed by the growth of

  1. Moss

  2. Ferns

  3. Gymnosperms

  4. Algae

Answer: A

Growth of Lichens on rocks growth of moss

Growth of Lichens on Rocks Growth of Moss

Growth of Lichens on rocks growth of moss

Question 27:

Marked temperature changes in aquatic environment can affect

  1. Breeding of animals

  2. More growth of aquatic plants

  3. Process of digestion in animals

  4. Availability of nutrients

Answer: A

Image the breeding of animals

Image the Breeding of Animals

Image the breeding of animals

Question 28:

Soil erosion can be prevented by

  1. Raising forests

  2. Deforestation

  3. Excessive use of fertilizer

  4. Overgrazing by animals

Answer: A

Image the prevention of soil erosion

Image the Prevention of Soil Erosion

Image the prevention of soil erosion