P S Verma and V K Agarwal solutions for Biology [English] Class 9 chapter 6 - Natural Resources [Latest edition]

Write down the composition of air.

How does oxygen and carbon dioxide remain nearly constant in the atmosphere?

How does the average temperature of Earth remain fairly steady?

How are winds produced?

Set up an experiment to measure gain and loss of heat by water, sand and air.

Demonstrate the formation of convective currents.

Enumerate the factors that influence movement of air.

How is rain produced?

Set up an experiment to demonstrate the effect of low pressure and particulate nuclei over water vapours.

Describe the major components of air pollution.

Write a brief note on acid rain.

Explain what is smog. Give its effects.

What are the effects of air pollution on human beings?

Explain the direction of air movement during the day and night in coastal areas.

Give role of atmosphere in climatic control.

Briefly explain main layers of the atmosphere.

Explain natural and human-made sources of air pollution.

How are clouds formed?

What is global warming? Give its effects.

Briefly explain depletion of ozone layer and its effects.

Explain phenomenon of acid rain.

Explain rain water harvesting.

What is climate?

Define the Weather.

How are CFCs harmful?

What is weathering? Elucidate in the various types of weathering.

What is soil erosion? Explain means of preventing it.

How do organisms contribute in the formation of soil?

Discuss how water is replenished in sea

Write a note on nitrogen fixation?

How is nitrogen replenished in atmosphere.

Describe the methods of carbon replenishment of atmosphere.

What are the possible dangers of global warming?

How is carbon dioxide concentration of atmosphere rising?

Why is ozone layer called ozone umbrella/shield?

What would be the effects on widening of ozone hole?

Explain water cycle in detail.

Draw diagram of Nitrogen cycle.

Draw diagram of carbon cycle.

Name four types of bacteria involved in nitrogen cycle.

Draw a diagrammatic sketch of oxygen cycle in nature.

Make sketch of hydrological cycle in nature.

Briefly describe three aspects of nutrient cycles.

Describe biological water cycles.

Prepare a flow chart of various natural resources.

Why is air called breath of life? Enumerate functions of air or atmosphere.

Describe the causes and effects of air pollution.

Explain ozone layer, its depletion and effects of ozone depletion.

Give an account of various sources and harmful effects of water pollution.

Explain the following :

(i) Eutrophication ;

(ii) Biomagnification

What is soil? How does it form?

Give various sources and harmful effects of soil pollution.

Define soil erosion. Give its causes, effects and preventive measures.

Describe nitrogen cycle.

Mention briefly the role of decomposers of cycling of materials.