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Chapter 17: Forests Our Lifeline

Q.1. Explain how animals make forest clean and regenerate.

Ans:

Animals help in cleaning forest in many ways. They are also known as cleansing agents. Degeneration is caused by microorganisms. Pollination is caused by animals which help in growing many numbers of plants. Carnivores live by depending on herbivores. Thus, forest has mutual relationships between flora and fauna.

 

Q.2 Explain how floods are prevented by forests.

Ans:

Lots of water are absorbed by forests. Flowing is slowed done mainly done by roots of the trees which majorly help in percolation. Thus, forests help in preventing floods.

 

Q.3. Explain decomposers and their work by giving two examples.

Ans.

Organisms which feed on dead bodies are called as Decomposers. They replenish the nutrients by cleaning the forests off decaying dead bodies. Two examples are beetles and bacteria.

 

Q.4. How do forests maintain the balance between oxygen and carbon dioxide in the atmosphere?

Ans:

During photosynthesis, plants release oxygen and take in carbon dioxide in the atmosphere.The animals inhale oxygen and they release carbon dioxide during respiration. In this way, the cycle goes on. Thus, it maintains balance through this cycle.

 

Q.5. Why  no waste remains in forests?

Ans:

This because of the role of decomposers. They convert the dead remains of plants and animals into humus which naturally adds to the soil. Thus, there is no waste in the forest.

 

Q.6. What are the products that we get from forests?

Ans:

Plant products,  Food, Fodder, Medicines, Description, Animals and animal products, Perfumes and cosmetics, Dying and tanning Utensils,  handicrafts Construction materials, Ornamentals, vegetable foodstuff and beverages provided by fruits, nuts, seeds, roots animal and bee fodder provided by leaves, fruits etc., Medicinal plants (e.g. leaves. bark, roots) used in traditional medicine and/or by pharmaceutical companies, Aromatic plants providing essential (volatile) oils and other products used for cosmetic purposes,Plant material (mainly bark and leaves) providing tannins and other plant parts (especially leaves and fruits) used as colorants, Heterogeneous group of products including thatch, bamboo, and rattan. wrapping leaves, fibers (e.g. Aromas, Buffalo, Silk cotton floss, Screw Pine) thatch, bamboo, fibers’, Entire plants (e.g. orchids, ferns, and philodendron) and parts of the plants (e.g. pots made from roots) used for ornamental purposes, Substances such as gums (water soluble), resins (water insoluble) and latex (milky or clear juice).  Honeybees wax Products are provided by bees. Bush meat Meat is provided by vertebrates, mainly mammals

 

Q.7. Fill in the blanks:

  1. The flowering of plants is done by honeybees, butterflies, insects by the method called________
  2. The basics forest purifier is___________
  3. Animal droppings and leaves decay enriches the________

Ans: 1. By Pollination         2. Through air, water            3. Humus in soil

 

Q.8. Why should we worry about the conditions of forests which are really far away from us?

Ans:

Deforestation leads to forest floods, Soil erosion, global warming which automatically lead to a decrease in animal and plant populations. This affects humans directly or indirectly. Thus we should be more concerned and worried about the condition of our forests.

 

Q.9. Why there is much more variety of animals and plants?

Ans:

Forest life is sustained by animals and plants through the oxygen and carbon dioxide cycle. They convert the decayed matter into humus and thus increase the fertility of the soil. This leads to an increase in the variety of plant and animal species.

 

Q.10. Mark the directions and arrows of the given diagram using the labels given below: 1.watertable 2.oxygen 3.soil 4.atmosphere 5.CO2 6.rain 7.plants.

14

Ans:  

15  

                                 

Q.11.Pick the odd one out. Which is not a product of forests?

  1. Plywood 2. Wax 3. Honey  4. Petrol

Ans: 4. Petrol

 

Q.12. Pick out the incorrect statement.

  1. Soil is being protected by forests from soil erosion.
  2. Animals are not dependent on plants whereas plants are dependent on animals.
  3. The water cycle and climate are influenced by forests.

  Ans: 2. Animals are not dependent on plants whereas plants are dependent on animals.   

 

Q.13. Dead plants are being acted upon by micro-organisms to produce

  1. Wood
  2. Mushrooms
  3. Humus
  4. Sand

Ans:  3.Humus.

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