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GSEB Solutions for Class 8 Science and Technology – Conservation of Environment

GSEB Solutions for Class 8 Science and Technology – Conservation of Environment (English Medium)

GSEB SolutionsMathsScience
Exercise 80:

Solution 1(a):

The presence of high concentration of harmful or poisonous substances such as smoke, dust, gases like carbon dioxide in the environment is called pollution.

Solution 1(b):

The various kinds of pollution are air pollution, water pollution, soil pollution and noise pollution.

Solution 1(c):

Plastic is a daily requirement for storage of items and is used as water bottles, shopping bags, compact discs, cups, kitchen appliances, plumbing pipes, yoghurt containers and toothbrush bristles.

Solution 1(d):

pellets which can be made into other products.

Exercise 81:

Solution 1(a):

The picture above shows garbage. The most garbage thrown is plastic items like shopping bags, water bottles, food storage containers, chocolate wrappers, etc.

Exercise 83:

Solution 1(a):

The various benefits of preparing paper bags are –

  1. They are reusable and biodegradable.
  2. They are not harmful to the environment as it can be reused.
  3. They are very cheap.
  4. They can be recycled to make papers.

Exercise 85:

Solution 1(a):

Electronic items such as computer, mobile phones, laptops, batteries and chips.

Solution 1(b):

Like plastics, we throw the electronic items outside and they end up in landfills. The harmful metals pose a threat to the environment. The electronic items also emit harmful radiations that can be hazardous to the living environment.

Solution 1(c):

We can minimize e-waste by repairing unused computers, TV sets, and mobile phones. We can also donate electronic appliances to the victims of natural calamities, etc.

Exercise 88:

Solution 1:

We can reduce plastic use by the following ways –

  1. We can bring paper bags to collect groceries.
  2. We should avoid the use of plastic bottles for beverages.
  3. We can use containers for carrying away of food in restaurants and hotels.
  4. If plastics are used, they should be discarded into non-biodegradable dustbins for collection by municipal workers.
  5. We can use wood or glass instead of plastic cutting boards.

Solution 2:

Biomedical wastes are very harmful to the environment. If the waste is not disposed properly then:

  1. The rag-pickers may get hurt while picking the waste.
  2. The stray animals that survive on the waste garbage may swallow the harmful medical waste.
  3. These wastes may spread harmful diseases like AIDS, Hepatitis.
  4. It may also lead to contamination of air, water and soil which may affect all forms of life.

Solution 3:

Plastics are non-biodegradable wastes that cannot be decomposed properly. It is the most used substance for household items but it has a very bad effect on the environment. The harmful effects of plastics are –

  1. The plastics, when thrown, go into the landfill and find their way to enter into the water sources, streets, roads.
  2. The plastics, when burnt, release toxic fumes that harm the living world.
  3. Due to accidental consumption of plastics by the stray animals, they are killed.
  4. The plastics are said to be non-biodegradable as their decomposition takes years and years.
  5. Plastics affect human health; they increase the risk of emphysema and cancer due to breathing of toxic fumes.

Solution 4:

The world’s population is rapidly growing which results in increased pressure on the environment, in the first place, on natural resources including water, food, energy and various materials. The main environmental challenges include –

  1. Loss of wildlife habitat.
  2. Loss of forests.
  3. Exploitation of natural resources.
  4. Increased emission of carbon dioxide.

We can protect our environment by –

  1. We can minimize the usage of electrical energy by swithching off the electrical appliances when not in use.
  2. The garbage must be discarded properly by throwing it in particular buckets and tubs.
  3. Use of plastics must be avoided as it harms the environment.
  4. The environment is also affected due to biomedical wastes which should be disposed in separate coloured containers.
  5. e-wastes can be reused by repairing electronic items such as mobile phones, TV sets, etc.

Solution 5:

e-wastes include the unused electronic appliances like television, computers, mobile phones, electronic chips. The electronic items contain harmful metals like platinum, gold, mercury which when consumed by stray animals cause death. If they are not disposed off properly, then it can lead to various health disorders in humans and animals when burnt.