GSEB Class 7 Social Science Solutions Chapter 11 પર્યાવરણનાં ઘટકો અને આંતરસંબંધો

1. Answer the following questions in one sentence:

Question 1. Write the components of the environment.
Answer: The four primary parts of the environment are the lithosphere, hydrosphere, atmosphere, and biosphere.
In simple words: The environment is made up of four main things: land, water, air, and all living things.

Exam Tip: Remember these four components as the fundamental elements that constitute our planet's environment.

Question 2. What are the main sources of fresh water?
Answer: Glaciers, underground water, freshwater lakes, rivers, and natural springs are the primary sources of fresh water.
In simple words: Ice, water from under the ground, fresh lakes, rivers, and springs are the main places we get fresh water from.

Exam Tip: Always list multiple diverse sources when asked about natural resources to demonstrate comprehensive knowledge.

Question 3. What is the time interval between two tides?
Answer: The time duration between two tides is roughly 12 hours and 25 minutes.
In simple words: There is about 12 hours and 25 minutes between one high tide and the next.

Exam Tip: Be precise with numerical answers; small differences can sometimes change the meaning in scientific contexts.

Question 4. Irritability is an effect of which pollution on human life?
Answer: Irritability is an impact of noise pollution (sound pollution) on human existence.
In simple words: When people get easily annoyed, it can be caused by too much noise.

Exam Tip: When discussing pollution effects, clearly link the type of pollution to its specific impact on human health or daily life.

Question 5. What is soil pollution?
Answer: Soil pollution means the quality of land or its essential nutrient parts becoming worse due to various causes.
In simple words: Soil pollution happens when the ground becomes dirty or loses its good nutrients because of different problems.

Exam Tip: Define environmental terms accurately, highlighting the core concept (e.g., quality degradation for pollution) and mentioning its causes.

2. Answer the following questions:

Question 1. What is man-made environment?
Answer: The human-made environment includes all those things that people create by using their intelligence and science, changing the living and non-living parts of the natural surroundings, and the outcomes that result from these modifications. Early humans during the Stone Age moved around, searching for food to sustain themselves. They lived their lives according to nature to fulfill their needs. Their requirements were only what the surrounding environment could easily provide. Over time, as human existence changed, their needs also grew. People learned how to utilize and alter their surroundings. They made significant discoveries like fire, farming, and the wheel. Based on these advancements, modern humans created agriculture, animal farming, small home businesses, large factories, transportation methods, roads, and places to live. This process is presently happening very fast. The human-made environment is also often called the cultural environment.
In simple words: The man-made environment is everything humans build or change using their smarts and science. This includes farms, cities, roads, and factories. It's also called the cultural environment.

Exam Tip: When explaining human-made environments, start with a clear definition, trace its historical development, and list common examples of human interventions and creations.

Question 2. Write measures to prevent soil pollution.
Answer: Measures to prevent soil pollution are as follows:

• Plastic and chemical substances should only be used in necessary amounts.
• Factories, industries, and settlements should, as much as possible, be built on barren, non-fertile land.
• In farming, instead of chemical fertilizers, organic and traditional manures, along with green manure, should be used.
• Pesticides used to protect crops from insects and pests should only be used as required.
• Solid waste should be sorted and reused.
• Instead of throwing unwanted plastic and solid waste on the ground, it should be burned or, where possible, recycled for reuse.
• Drip and sprinkler irrigation methods should be employed in farming.

Exam Tip: When listing prevention methods, provide a balanced mix of individual actions (like reusing) and broader policy/technological solutions (like building on barren land or using drip irrigation).

Question 3. What steps should be taken to prevent air pollution?
Answer: Steps that should be taken to prevent air pollution are:

• To stop air pollution, the government should make new laws and strictly enforce them.
• Equipment that filters smoke and toxic gases should be developed.
• The use of coal and petrol-diesel should be kept very limited.
• The use of pollution-free fuels like CNG, PNG, solar energy, and electricity in vehicles should be encouraged.
• Strict enforcement of PUC (Pollution Under Control) for vehicles should be done.
• Awareness should be spread so that people use public transportation more for travel.
• To control the amount of CO2 in the air, the number of forests and greenery should be increased.

Exam Tip: For environmental solutions, categorize your points into legislative, technological, behavioral, and natural approaches to provide a complete answer.

Question 4. Write your efforts to prevent noise pollution.
Answer: My efforts to prevent noise pollution are as follows:

• I will ensure that all vehicles in my home are serviced (repaired) on time.
• I will play radio, television, mobile phones, musical instruments, etc., at a low volume.
• I will suggest installing sound-absorbing devices and curtains in cinema halls and public auditoriums.
• I will avoid unnecessary noise during social events, festivals, inauguration ceremonies, or weddings.
• I will not burst firecrackers during celebration programs and processions.
• I will strictly enforce 'No Horn' and 'Silence Zone' rules near places like schools and hospitals.
• I will try to control vehicle noise by planting trees on both sides of main roads.

Exam Tip: When asked about personal efforts, use "I will" statements and ensure your examples cover various daily situations and public settings.

3. Give Reasons:

Question 1. Tides occur in the sea.
Answer: Sea water rises twice a day and falls twice a day. When sea water rises, it is called 'tide,' and when it falls, it is called 'ebb.' During high tide, the sea level rises and moves towards the shore. During ebb tide, the sea level drops and moves away from the shore. Tides happen due to the gravitational force of the sun and the moon. Tides are not the same at all places and on all days. The highest tides occur on full moon and new moon days.
In simple words: Ocean water goes up and down twice a day, which we call tides. This happens because the moon and sun pull on the water with their gravity. The highest tides happen during a full moon or new moon.

Exam Tip: When explaining natural phenomena, clearly define terms (tide, ebb), describe the process, and identify the primary scientific cause (gravitational pull of sun and moon).

Question 2. High tides occur on the days of Satam-Atham.
Answer: On every new moon and full moon day, the sun, Earth, and moon are in a straight line. Because of this alignment, the gravitational pull from the sun and moon combine, causing larger ocean waves. On these new moon and full moon days, since the gravitational force of the moon and the sun acts in the same direction on Earth, large, or 'spring' tides occur.
In simple words: Big tides happen on full and new moon days. This is because the sun, Earth, and moon line up. Their combined pull makes the ocean water rise more, causing higher tides.

Exam Tip: Link the specific days (new moon, full moon) to the alignment of celestial bodies and the combined gravitational force to fully explain the cause of spring tides.

4. Fill in the blanks with appropriate words:

Question 1. The atmosphere absorbs the sun's _______ rays and protects living beings.
Answer: Ultraviolet
In simple words: The atmosphere stops harmful ultraviolet rays from the sun, keeping life safe.

Exam Tip: Know the specific functions of Earth's atmospheric layers, such as the absorption of harmful radiation by the ozone layer.

Question 2. Noise pollution is also called _______.
Answer: Racket
In simple words: We often call noise pollution "racket" because it means loud, unwanted sounds.

Exam Tip: Be aware of synonyms for common environmental terms, especially those that might be used interchangeably in different contexts.

Question 3. When sea water rushes towards the shore, it is called _______.
Answer: Tide
In simple words: When the sea water comes in towards the land, we call it a tide.

Exam Tip: Clearly distinguish between the terms 'tide' (water rushing in) and 'ebb' (water receding) when describing ocean movements.