Discuss the effects of deforestation on the following:
(a) Wild animals
(b) Environment
(c) Villages (Rural areas)
(d) Cities (Urban areas)
(e) Earth
(f) The next generation
(a) Wild animals:
Forests are the main natural habitat for the wild animals. Deforestation means cutting of trees from the particular area like forest. Trees are cut down for the various purposes like agricultural, industrial and many other. If trees are removed from their habitat then the number of wild animals automatically decreases.
(b) Effects of deforestation on environment:
Deforestation means the removal of the trees. If trees are removed then the level of the carbon dioxide increase or rise up in the environment. Increase in the level of the CO2 is the main reason of increasing the temperature on the earth which leads to the global warming. Deforestation disturbs the water cycle. Deforestation also leads to the drastic changes in the environment like floods, droughts.
(c) Effects of deforestation on villages (Rural areas):
By removing trees, the top layer of the soil will be removed easily by high speed winds or by water. Roots of the plants bind to the soil particles together. In the absence of trees soil erosion occurs readily and land becomes infertile. A fertile land is a source of living for the people who lives in villages.
(d) Effects of deforestation on cities (Urban areas):
Due to deforestation, the level of the carbon dioxide increase in the environment which leads to an increment of the earth’s temperature which is the main cause of the global warming. Carbon dioxide is a polluted gas. In cities, pollution from the vehicles, factories, industries occur generally. Increasing temperature of the earth also disturb the water cycle.
(e) Effects of deforestation on earth:
Deforestation leads to the soil erosion, drought. Flood like dangerous conditions. By deforestation an increment in the risk of the natural calamities. Due to deforestation, the air becomes polluted and a number of diseases on earth.
(f) Effects of deforestation on next generation:
Environmental conditions will change slowly if we remove trees from the earth. It may lead to the global warming, soil erosion, drought, flood, green house effect and many more climatic change conditions. Hence, the next generation will have to face the deforestation consequences.
Answer in brief:
(a) Why should we conserve biodiversity?
(b) Protected forests are also not completely safe for wild animals. Why?
(c) Some tribals depend on the jungle. How?
(d) What are the causes and consequences of deforestation?
(e) What is Red Data Book?
(f) What do you understand by the term migration?
Find out the information about the national parks in your state. Identify and show their location on the outline map of India.
Complete the word puzzle:
Down
1. Species on the verge of extinction.
2. A book carrying information about endangered species.
5. Consequence of deforestation.
Across
1. Species which have vanished.
3. Species found only in a particular habitat.
4. Variety of plants, animals and microorganisms found in an area.
Differentiate between the following:
(a) Wildlife sanctuary and biosphere reserve
(b) Zoo and wildlife sanctuary
(c) Endangered and extinct species
(d) Flora and fauna
Why should paper be saved? Prepare a list of ways by which you can save paper.
In order to meet the ever-increasing demand in factories and for shelter, trees are being continually cut. Is it justified to cut trees for such projects? Discuss and prepare a brief report.
Explain how deforestation leads to reduced rainfall.
What will happen if:
(a) we go on cutting trees.
(b) the habitat of an animal is disturbed.
(c) the top layer of soil is exposed.
How can you contribute to the maintenance of green wealth of your locality? Make a list of actions to be taken by you.
Fill in the blanks:
(a) A place where animals are protected in their natural habitat is called .
(b) Species found only in a particular area is known as .
(c) Migratory birds fly to far away places because of changes.
Which of the following can be beaten into thin sheets?
(a) Zinc (b) Phosphorus (c) Sulphur (d) Oxygen
Fill in the blanks
(a) Most liquids that conduct electricity are solutions of , ______________ and ______________.
(b) The passage of an electric current through a solution causes ______________ effects.
(c) If you pass current through copper sulphate solution, copper gets deposited on the plate connected to the terminal of the battery.
(d) The process of depositing a layer ofany desired metal on another material by means of electricity is called .
Give two examples each of situations in which you push or pull to change the state of motion of objects.
Fill in the blanks:
(a) Friction opposes the _____________ between the surfaces in contact with each other.
(b) Friction depends on the _____________ of surfaces. (c) Friction produces __________.
(d) Sprinkling of powder on the carrom board ________ friction.
(e) Sliding friction is ___________ than the static friction.
List conditions under which combustion can take place.
Indicate whether the following statements are True (T) or False (F).
(a) Unicellular organisms have one-celled body. (T/F)
(b) Muscle cells are branched. (T/F)
(c) The basic living unit of an organism is an organ. (T/F)
(d) Amoeba has irregular shape. (T/F)
Which of the following cannot be charged easily by friction?
(a) A plastic scale
(b) A copper rod
(c) An inflated balloon
(d) A woollen cloth.
Suppose you are in a dark room. Can you see objects in the room? Can you see objects outside the room. Explain.
What are the different ways in which water gets contaminated ?
Explain the importance of reproduction in organisms.
A pendulum oscillates 40 times in 4 seconds. Find its time period and frequency.
Match the organisms in Column I with their action in Column II.
Column I Column II
(i) Bacteria (a) Fixing Nitrogen
(ii) Rhizobium (b) Setting of curd
(iii) Lactobacillus (c) Baking of bread
(iv) Yeast (d) Causing Malaria
(v) A protozoan (e) Causing Cholera
(vi) A Virus (f) Causing AIDS
(g) Producing antibodies
Identify the part which vibrates to produce sound in the following instruments:
(a) Dholak (b) Sitar (c) Flute
Define asexual reproduction. Describe two methods of asexual reproduction in animals.
Is it safe for the electrician to carry out electrical repairs outdoors during heavy downpour? Explain.
When the free ends of a tester are dipped into a solution, the magnetic needle shows deflection. Can you explain the reason?
Write notes on—
(a) Adam’s apple.
(b) Secondary sexual characters.
(c) Sex determination in the unborn baby.
Sometime, a crackling sound is heard while taking off sweater during winters. Explain.
Mark the following statements as true (T) or false (F):
(a) Pole Star is a member of the solar system. ( )
(b) Mercury is the smallest planet of the solar system. ( )
(c) Uranus is the farthest planet in the solar system. ( )
(d) INSAT is an artificial satellite. ( )
(e) There are nine planets in the solar system. ( )
(f) Constellation Orion can be seen only with a telescope. ( )
Two mirrors meet at right angles. A ray of light is incident on one at an angle of 30° as shown in Fig. 16.19. Draw the reflected ray from the second mirror.