NIOS Biology Intext Solutions Chapter 26
INTEXT QUESTIONS 26.1
1. Given below are certain wrong statements. Identify the mistake and write the correct statement below each.
(i) Plastic is a natural resource.
(ii) Forest is an exhaustible non-renewable resource.
(iii) The exhaustible resources, which are not replaced after consumption, are known as renewable resources.
Ans:
- (i) Plastic is an artificial resource.
- (ii) Forest is an exhaustible renewable resource.
- (iii) The exhaustible resources, which are not replaced after consumption, are known as non-renewable resources.
OR
- The resources, which are replaced after consumption, are known as renewable resources
2. Classify the following under the three respective categories of natural resources:
Air, iron, sand, petroleum, wind, clay, fish, forest, gold, pearls.
Inexhaustible Renewable Non-renewable
Ans:
| Inexhaustible | Renewable | Non-renewable |
| Air | Fish | Iron |
| Sand | Forest | Petroleum |
| Wind | Pearls | Gold |
| Clay |
INTEXT QUESTIONS 26.2
1. Why should we conserve natural resources? State any two reasons.
Ans:
- (i) To maintain ecological balance to support life.
- (ii) To preserve different kinds of species.
2. Given below are certain incomplete words. Complete them by taking clues from the statement given below for each. Each blank space represents one letter only.
(i) __ __ __ p k __. (A movement started by women to stop the felling of trees by hugging them)
Ans: Chipko
(ii) T__ __ __ i. (A sacred plant worshipped in India)
Ans: Tulsi
(iii) Kh __ ch __ __ pa__ __ i. (A lake in Sikkim that was declared sacred by the people)
Ans: Khecheopalri
INTEXT QUESTIONS 26.3
1. How do the following cause soil erosion?
Wind Overgrazing Water
Ans:
- Wind: Carries away the loose topsoil
- Overgrazing: Removes the protective vegetation, thus helping in erosion by wind and water
- Water: Raindrops carry away the soil not covered by vegetation.
2. Match the items of Column A with those of Column B.
| Column-A | Column-B |
| (i) Terracing | (a) Decayed vegetable or animal matter |
| (ii) Erosion | (b) Cutting down forests |
| (iii) Deforestation | (c) Practised in hilly areas |
| (iv) Humus | (d) To wear away |
Ans:
| (i) Terracing | (c) Practised in hilly areas |
| (ii) Erosion | (d) To wear away |
| (iii) Deforestation | (b) Cutting down forests |
| (iv) Humus | (a) Decayed vegetable or animal matter |
INTEXT QUESTIONS 26.4
1. Why do we consider fresh water as a renewable resource?
Ans: It is produced continuously through the hydrologic cycle.
2. Give three methods of water conservation.
Ans:
- (i) Constructing dams and reservoirs
- (ii) Rainwater harvesting
- (iii) Judicious use
INTEXT QUESTIONS 26.5
1. Some of the following words/terms are related to conservation of biodiversity, and some are threats to biodiversity. Identify the points relating to conservation by mentioning ‘C’ and the threat to biodiversity by mentioning ‘T’ against the points.
(i) Wildlife sanctuaries
(ii) Population explosion
(iii) Industrialisation
(iv) Zoo
(v) Tissue culture
(vi) Pollution
Ans:
- (i) C
- (ii) T
- (iii) T
- (iv) C
- (v) C
- (vi) T
INTEXT QUESTIONS 26.6
1. What is Red Data Book?
Ans: It is published by the IUCN, which gives information on endangered plants and animals.
2. Define the term Wildlife.
Ans: The plants, animals, and microbes other than the cultivated plants and domesticated animals constitute the wildlife.
3. Below are certain incomplete words. Complete them by taking clues from the statement given below for each. Each blank represents the letter only.
(i) A __ __ or __ __ __ at __ on (Tree planting programme)
Ans: Afforestation
(ii) Be __ __ ado __ __ a (An endangered Indian plant)
Ans: Belladonna
(iii) Rh __ no __ __ r __ __ (An endangered animal)
Ans: Rhinoceros
INTEXT QUESTIONS 26.7
1. Expand the following.
(i) WWF.
(ii) CITES.
(iii) IUCN.
Ans:
- (i) World Wildlife Fund
- (ii) Convention on International Trade in Endangered Species
- (iii) International Union for Conservation of Natural Resources
2. Match the items of Column A with those of Column B.
| Column – A | Column – B |
| (i) Periyar sanctuary | (a) Rajasthan |
| (ii) Kanha National Park | (b) Orissa |
| (iii) Similipal National Park | (c) Uttaranchal |
| (iv) Bharatpur bird sanctuary | (d) Kerala |
| (v) Corbett National Park | (e) Madhya Pradesh |
Ans: (i) (d), (ii) (e) (iii) (b)(iv) (a)(v) (c)
INTEXT QUESTIONS 26.8
1. A and B are two friends. In their daily life, both have different opinions on certain matters. Considering the necessity of sustainable development, give your suggestions in the given space.
A says – Polythene bags should be used to carry vegetables.
B says – Jute bags should be used to carry vegetables.
Who is right and why?
Ans: B is right, because jute bags are biodegradable and eco-friendly.
Though science has invented biodegradable polythene bags, not all are biodegradable, hence they cause pollution.
2. Mention any two activities which will help in sustainable development.
Ans:
- Reducing excessive use of resources and enhancing resource conservation.
- Recycling and reuse of waste materials.
- Scientific management of renewable resources, especially bio-resources.
- Planting more trees.
- Green grassy patches are to be interspersed between concrete buildings.
- Using more environmentally friendly materials or biodegradable materials.
- Use of technologies that are environmentally friendly and based on efficient use of resources.
INTEXT QUESTIONS 26.9
1. Coal is a non-renewable source of energy, whereas wood charcoal is renewable. Why?
Ans: Coal cannot be regenerated after consumption. But wood charcoal is obtained from wood, and wood can be obtained continuously from trees/forests.
2. How are the following useful in our day-to-day life?
(i) CNG
(ii) PNG
(iii) LPG.
Ans:
- CNG: Cooking, Transportation
- PNG: Cooking
- LPG: Cooking, Lighting, Transportation
3. A and B are two friends. In their daily life, both have different opinions on certain matters. Considering the necessity of sustainable development, give your suggestions in the given space.
A says – Coal should be used as a fuel to cook our food
B says – LPG should be used as a fuel to cook our food.
Who is right and why?
Ans: B is right. LPG causes less pollution than coal.
INTEXT QUESTIONS 26.10
1. Why do we consider sun as the best source of energy?
Ans: It is available free of cost and in ample quantity, everlasting. It has no boundaries and is also free from political barriers.
2. What is meant by ‘radioactive pollution’?
Ans: The radioactive elements, when not disposed of properly, cause disintegration in the soil and water and thus cause pollution.
3. What are the advantages and disadvantages of nuclear energy?
Ans: Approximately 3% of India’s electricity comes from nuclear power, and about 25% is expected to come by 2050. India has sufficient Thorium to generate electricity without causing pollution.
4. The following table contains the different sources of energy and their uses. Put a tick mark under the source against the appropriate use(s).
| Geothermal | Bio gas | Bio-diesel | |
| (i) Generation of Electricity | |||
| (ii) Fuel for Cooking | |||
| (iii) Fuel for Vehicles |
Ans:
| Geothermal | Bio gas | Bio-diesel | |
| (i) Generation of Electricity | √ | √ | √ |
| (ii) Fuel for Cooking | √ | ||
| (iii) Fuel for Vehicles | √ |
5. Mention any three ways of conservation of electric energy in your home.
Ans:
- (i) Judicious use of electricity
- (ii) Use of a fluorescent lamp instead of an incandescent lamp
- (iii) Create awareness about the proper use of electricity, or any other.
