Ncert- science – class 7- Chapter 12 – Forests: Our Lifeline 2 Welcome to your Ncert- science – class 7- Chapter 12 – Forests: Our Lifeline 2 1. Which of the following statements are correct? I. If forests disappear, the amount of carbon dioxide in air will increase, resulting in the increase of earth's temperature.II. In the absence of trees and plants, animals will get no food and shelter.III. In the presence of trees, the soil will not hold water, which will cause floods.IV. Deforestation will endanger our life and environment. I, II and IV I, II and III Only I and II II, III and IV None 2. Ecology TermsTermDefinitionCanopyPrevent soil erosionCrownFeed on dead plants and animalsRootsRoof of tall treeDecomposerBranchy part above stem 1 - B, 2 - D, 3 - A, 4 - C 1 - D, 2 - C, 3 - A, 4 - B 1 - C, 2 - D, 3 - A, 4 - B 1 - C, 2 - D, 3 - B, 4 - A None 3. Forests prevent floods. How do they do so? They inhibit rainfall. Trees do not allow rain to reach ground at all. Oxygen liberated by trees reacts with the rain water and hence, reduce the amount of water. They help the soil to hold water. None 4. Match the items in Group (A) with the items in Group (B) on the basis of the parts of the plant they are obtained from.Group (A)Group (B)Matchstick(i)Bark Oil(ii)leaves Paper(iii)rootsTea(iv) Seeds (v)Stem or branch 1 - (iii), 2 - (ii), 3 - (v), 4 - (iv) 1 - (v), 2 - (iv), 3 - (i), 4 - (ii) 1 - (v), 2 - (iv), 3 - (ii), 4 - (iii) 1 - (iii), 2 - (v), 3 - (ii), 4 - (i) None 5. A natural resource is a substance/commodity that is a gift of nature which is very useful to mankind. True False Either Neither None 6. Trees in the forest have ______ of different type, size and shape to make understories. crowns stems canopies flowers None 7. Different layers of vegetation provide _________ and________for animals. Shelter and air Food and shelter Food and water Air and water None 8. Find the odd one out.Neem, Tulsi, Amla and Teak. Neem Amla Tulsi Teak None 9. Which of the following is not a medicinal plant? Neem Eucalyptus Amla Teak None 10. Which of the following roles is played by canopy during rain? Restoration of water table Seepage of water Slowing down the speed of rain drops Absorption of water None 11. Deforestation leads to the increased percentage of which of the following components of the environment? Nitrogen Carbon dioxide Oxygen None of the above None 12. Study the following statements regarding food chains and select the correct ones.(i) Removal of 80% tigers from an area resulted in greatly increased growth of vegetation.(ii) Removal of most of the carnivores resulted in an increased population of deers.(iii) The length of food chains is generally limited to 3−4 trophic levels due to energy loss.(iv) The length of food chains may vary from 2 to 8 trophic levels. (i) and (iii) (i) and (ii) (ii) and (iii) (iii) and (iv) None 13. Which of the following groups of wild animals represents the inhabitants of only deeper areas of the forest? Boar, bison, jackal, porcupine Rabbit, beer, tiger, donkey Cat, kangaroo, lion, elephant Dog, snake, monkey, deer None 14. Forest officers are trained to recognise the presence of animals in the forest from various characteristics. Which of the following characteristics are used by them to recognise the presence of animals? (i) Body odour(ii) Footprints(iii) Droppings Only (iii) Only (ii) and (iii) Only (i) and (ii) (i), (ii), and (iii) None 15. What is the role of humus in the forest? To ensure the release of nutrients into the soil To ensure the growth of microorganisms To ensure the presence of earthworms in the soil To ensure the warmth in the soil None Time's up Please Share This Share this content Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Leave a Reply Cancel replyCommentEnter your name or username to commentEnter your email address to commentEnter your website URL (optional) Save my name, email, and website in this browser for the next time I comment.
