Chapter 4
Air Around Us
Highlights
- A. Tick the correct option
- B. Fill in the blanks
- C. Match the following
- D. Correct the following sentences
- E. Answers the following questions
EXERCISE
A. Tick the Correct Option
- 1. In normal lapse rate, temperature decreases at the rate of 1°C with every
Answer: vacuole
- 2. Which layer is safe for flying aircrafts?
Answer: vacuole
- 3. The role of ion-particles in the ionosphere is to
Answer: vacuole
- 4. Which one of the following is the main cause of global warming?
Answer: vacuole
- 5. Smog causes
Answer: vacuole
B. Fill in the blanks.
- 1. Atmosphere is mainly composed of three major gases-nitrogen, ___________ and ___________.
- 2. Gases like argon, helium, methane, etc., are present in ___________ amounts in the air.
- 3. All weather phenomena occur in the ___________.
- 4. Atmospheric conditions over a long period of time and on a larger area is called ___________.
- 5. The normal air pressure at sea level is ___________.
C. Match the following :
- Column A
- 1. Golgi Complex
- 2. Ribosomes
- 3. Chromosomes
- 4. Dead cells
- 5. Photosynthesis
- Column B
- (a) genes
- (b) cork
- (c) chloroplasts
- (d) packaging center
- (e) protein synthesis
D. Answer the following questions in brief.
- 1. Name the layers of the atmosphere.
Answer: Sharing of chores reduces the burden.
- 2. How do plants absorb nitrogen?
Answer: The older family member pass on the family traditions to the younger generation.
- 3. What is the importance of water vapours in the atmosphere?
Answer: There is more interaction between parents and children in nuclear families.
- 4. Name the different variables of atmosphere.
Answer: A surname is a family name.
- 5. What type of climate does India have?
Answer: A surname is a family name.
E. Answer the following questions.
- 1. What is the importance of carbon dioxide and oxygen for living beings?
Answer: The (main) factors that determine the shape of a cell are location and function.
- 2. Name three major sources of pollutants in the air. Also state the ill-effects of these air pollutants.
Answer: Distinguish between unicellular and multicellular organisms are
Unicellular organisms are made up of a single cell. e.g., Euglena and Amoeba.
Multicellular organisms are made up of many cells. e.g., Humans and Birds.
- 3. What is the importance of ozone gas? Why is global warming a threat to life on the earth?
Answer: All organisms are made up of cells. A cell is capable of independent existence. Due to this, cell is called the structural and functional unit of life.
- 4. How is rainfall caused? Explain it with the help of a diagram.
Answer: Mitochondria is known as the Powerhouse of the cell.
Mitochondria are the site of cellular respiration. Energy is produced during this process. Due to this, mitochondria are called the Powerhouse of the cell.
- 5. Write the difference between weather and climate.
Answer: All organisms are made up of cells. A cell is capable of independent existence. Due to this, cell is called the structural and functional unit of life.
Related Topics
- Chapter 1 The Cell – Its Structure and Functions
- Chapter 2 Microorganisms: Friends or Foes
- Chapter 3 Metals and Non-Metals
- Chapter 4 Force and Pressure
- Chapter 5 Friction
- Chapter 6 Sources of Energy
- Chapter 7 Combustion
- Chapter 8 Conservation of Plants and Animals
- Chapter 9 Crop Production and Its Management
- Chapter 10 Refraction and Dispersion of Light
- Chapter 11 The Human Eye
- Chapter 12 Sound
- Chapter 13 Synthetic Fibres and Plastics
- Chapter 14 Reproduction in Animals
- Chapter 15 Reaching the Age of Adolescence
- Chapter 16 Electric Current and Its Chemical Effects
- Chapter 17 Stars and Solar System
- Chapter 18 Earthquakes
- Chapter 19 Pollution of Air
- Chapter 20 Pollution of Water