All questions of Waste and Waste Disposal for Primary 5 Exam

Nonbiodegradable materials do not decompose over a short period of time. Materials such as plastics, glass bottles and metals will often remain completely intact in the environment for many years. In fact, items like glass bottles may never biodegrade.

A is the correct answer

The most important reason for proper waste management is to protect the environment and for the health and safety of the population. Certain types of waste can be hazardous and can pollute the environment.  Cost savings – managing the waste your business produces can result in valuable materials to reuse.

Explanation:
Garbage is a mixture of different types of waste materials. Some of these waste materials can rot and decay completely without emitting any foul smell. When this happens, the waste materials can be converted into manure or mixed with soil to provide nutrients to plants. This is because the waste materials have broken down into their basic organic components, which are rich in nutrients that plants need to grow.

Benefits of using garbage as manure:
- Manure made from garbage is an organic fertilizer that is rich in nutrients, such as nitrogen, phosphorus, and potassium. These nutrients are essential for plant growth and development.
- Garbage manure is eco-friendly and helps to reduce waste in landfills.
- It is cost-effective and reduces the need for chemical fertilizers, which can be expensive and harmful to the environment.

Benefits of mixing garbage with soil:
- When garbage is mixed with soil, it helps to improve the soil's fertility and structure. This is because the organic components in the garbage help to retain moisture in the soil, prevent soil erosion, and increase nutrient availability.
- The soil becomes more porous, allowing air and water to penetrate easily, which benefits plant growth.
- Soil that has been enriched with garbage is better able to support a diverse range of plant species.

In conclusion, converting garbage into manure or mixing it with soil is an effective way to reduce waste, improve soil fertility, and promote plant growth. This is an eco-friendly and cost-effective solution that benefits both the environment and agriculture.

Coffee, Tea, Vegetable and fruit waste- all are biodegradable. So correct answer is option d

Understanding the Correct Answer: "Burn"
The sentence provided is about handling garbage, and the correct answer is "Burn." Let's break down why this option is the most appropriate.
Reasons to Avoid Burning Garbage
- Environmental Impact: Burning garbage releases toxic pollutants into the air, harming both the environment and human health. These emissions can contribute to air pollution and respiratory issues.
- Waste of Resources: Many items that are thrown away can be recycled or repurposed. Burning them eliminates the possibility of reusing valuable materials.
- Climate Change Contribution: The combustion of waste can release greenhouse gases, which contribute to climate change. This is detrimental to our planet's health and future.
Alternatives to Burning Garbage
- Collecting: Collecting garbage is the first step in waste management, ensuring it is removed from living spaces but does not address the disposal method.
- Decomposing: Decomposition naturally occurs in organic waste, which can be processed to enrich soil instead of being burned.
- Composting: Composting is an eco-friendly alternative that allows organic waste to break down naturally, creating nutrient-rich soil while avoiding harmful emissions.
Conclusion
In summary, the answer "Burn" highlights the negative aspects of this disposal method. It is essential to focus on sustainable practices like recycling, composting, and responsible waste management to protect our environment and promote a healthier future.

Option C"

Non-biodegradable and harmful nature of polythene and plastics

Polythene and plastics are synthetic materials that are widely used in our daily lives due to their durability, flexibility, and low cost. However, they pose a significant threat to the environment and living organisms due to their non-biodegradable and harmful nature.

1. Non-biodegradable nature:
- Polythene and plastics are composed of long chains of polymers that are resistant to natural degradation processes.
- Unlike organic materials such as paper or wood, which can be broken down by microorganisms, polythene and plastics do not decompose easily.
- As a result, they persist in the environment for hundreds of years, leading to the accumulation of plastic waste in landfills, oceans, and other natural habitats.

2. Environmental impact:
- Plastics and polythene waste, when improperly disposed of, end up in landfills or find their way into water bodies.
- These materials release harmful chemicals into the soil and water, leading to pollution and the destruction of ecosystems.
- Plastic waste can also entangle and suffocate marine animals, causing injury or death. Additionally, marine animals may mistake plastic debris for food, leading to ingestion and subsequent health issues.

3. Microplastics:
- When plastics and polythene degrade under sunlight, heat, or mechanical action, they break down into smaller fragments called microplastics.
- Microplastics are tiny particles that can range in size from a few millimeters to microscopic dimensions.
- These particles are so small that they can be easily ingested by marine organisms and can enter the food chain, ultimately affecting human health.

4. Chemical leaching:
- Plastics and polythene can release toxic chemicals into the environment over time.
- When exposed to heat or sunlight, plastic containers may release harmful substances like bisphenol A (BPA) and phthalates, which can have adverse effects on human health.

5. Visual pollution:
- Plastic waste is a major contributor to visual pollution, especially in urban areas.
- Plastic bags, bottles, and other discarded plastic items litter streets, parks, and other public spaces, diminishing the aesthetic appeal of the environment.

In conclusion, polythene and plastics are non-biodegradable materials that have a detrimental impact on the environment. Their persistence, along with the release of harmful chemicals and the formation of microplastics, poses serious threats to ecosystems, wildlife, and human health. It is essential to reduce plastic consumption, promote recycling, and adopt sustainable alternatives to mitigate these harmful effects.

Explanation:

Introduction:
Red worms, also known as compost worms or Eisenia fetida, are commonly used in composting and vermicomposting. They play a crucial role in breaking down organic waste materials and converting them into nutrient-rich compost. Creating a comfortable home for red worms is essential to ensure their health and optimal composting activity.

Options:
a) Dig a pit about 30 cm deep.
b) Dig a pit about 30 cm deep at a place which is very hot.
c) Dig a pit about 30 cm deep at a place which is very cold.
d) Dig a pit 30 cm deep at a place which is neither too hot nor too cold.

Explanation of the correct answer - Option D:
To create a comfortable home for red worms, it is important to provide them with suitable temperature conditions. Extreme temperatures, whether hot or cold, can be detrimental to their well-being. Therefore, the correct answer is option D, which suggests digging a pit 30 cm deep at a place which is neither too hot nor too cold.

Reasoning:
1. Red worms are sensitive to temperature fluctuations and thrive in moderate temperatures between 15-25 degrees Celsius.
2. If the pit is dug in a place that is very hot, the high temperatures can cause the worms to dry out and die. Excessive heat can also accelerate the decomposition process, making it difficult for the worms to keep up with the rate of decomposition.
3. On the other hand, if the pit is dug in a place that is very cold, the low temperatures can slow down the worms' metabolic activity, leading to decreased feeding and reproduction. In extreme cold conditions, the worms may even go into a state of dormancy or die.
4. Digging a pit about 30 cm deep at a place which is neither too hot nor too cold provides a stable and moderate environment for the red worms. This depth helps to provide insulation against temperature fluctuations from the surrounding environment.
5. Additionally, maintaining the pit at ground level or slightly elevated helps to prevent waterlogging, which can be harmful to the worms.

Conclusion:
Creating a comfortable home for red worms involves considering their temperature requirements. Option D, which suggests digging a pit 30 cm deep at a place which is neither too hot nor too cold, provides the best environment for the worms to thrive and carry out their composting activities effectively.

( C ) To Landfills
Safai-karamcharis collect the garbage in trucks and take it to a low lying open area , called a landfill ( Fig. 16. 1). there the part of the garbage that can be refused is separated out from the one that cannot be used as such.

Red worm

The answer is Dustbins because if we will throw trash anywhere we want can make many people sick because mosquitoes will spread in that area

Understanding Plastic Waste Reduction
To tackle the growing issue of plastic waste, option 'C'—minimizing its use—emerges as the most effective and sustainable solution. Here’s why:
Environmental Impact
- Reducing plastic use directly diminishes the amount of waste generated.
- Less plastic in circulation means reduced pollution in our oceans, rivers, and landscapes.
- It helps protect wildlife that is often harmed by plastic waste.
Sustainable Alternatives
- By minimizing plastic, we can encourage the use of biodegradable or reusable materials.
- Options like cloth bags, glass containers, and metal straws are eco-friendly alternatives.
- Shifting to these alternatives fosters a culture of sustainability among consumers.
Long-term Solutions
- Minimizing plastic use promotes a circular economy, where resources are reused and recycled.
- It encourages innovation in product design, leading to more sustainable practices in manufacturing.
- This approach not only addresses the current waste problem but helps prevent future issues.
Community Awareness
- By choosing to minimize plastic use, individuals can inspire others in their community to follow suit.
- Educational initiatives can spread awareness about the harmful effects of plastic and the benefits of reducing its use.
- Collective action can lead to significant changes at local, national, and global levels.
In conclusion, while options like burying, burning, or dumping plastic may seem like immediate solutions, they fail to address the root cause of plastic waste. Minimizing use fosters a more sustainable future by reducing waste, promoting alternatives, and encouraging community involvement.

Understanding the Maharaja’s Intention
The Maharaja’s primary intention behind organizing the grand dinner was to showcase the palace's hospitality. Here’s a detailed breakdown of this choice:
Importance of Hospitality
- A grand dinner is a traditional way to exhibit one's culture and values, particularly in royal settings.
- By hosting such an event, the Maharaja aimed to highlight the warmth and generosity associated with his reign.
Strengthening Relationships
- The dinner served as a platform for fostering relationships with both local and visiting dignitaries.
- It allowed the Maharaja to strengthen alliances and friendships, which are crucial for maintaining peace and prosperity in his kingdom.
Showcasing Culture
- The event provided an opportunity to display rich cultural heritage through food, music, and decor.
- This not only entertained the guests but also instilled a sense of pride within the Maharaja’s subjects about their traditions.
Creating Lasting Impressions
- A well-organized dinner can leave a lasting impression on attendees, ensuring the Maharaja’s reign is remembered positively.
- Guests would likely share their experiences, reinforcing the Maharaja’s reputation for hospitality.
Conclusion
In summary, the grand dinner organized by the Maharaja was primarily aimed at demonstrating the palace’s hospitality, which served multiple purposes including cultural representation, relationship building, and leaving a lasting impression on guests. This strategic move underscored the importance of hospitality in royal leadership and governance.

What is Recycling?
Recycling is a crucial process that helps in conserving resources and reducing waste. It involves converting old materials into new products, which has several environmental benefits.
How Recycling Works
- Collection: Used materials, like paper, plastic, glass, and metals, are collected from homes, businesses, and recycling centers.
- Sorting: The collected items are sorted based on their material type. This ensures that similar materials are processed together.
- Processing: Once sorted, the materials are cleaned and processed into raw materials. For example, plastic bottles can be shredded and melted down to create new plastic products.
- Manufacturing: The recycled raw materials are then used to manufacture new products. This can include anything from recycled paper to new aluminum cans.
- Purchasing: Finally, consumers can help by purchasing products made from recycled materials, thus closing the recycling loop.
Benefits of Recycling
- Conserves Resources: Recycling reduces the need for raw materials and helps conserve natural resources.
- Reduces Landfill Waste: By recycling, less waste ends up in landfills, which helps reduce pollution and extend the life of these sites.
- Saves Energy: Manufacturing products from recycled materials usually requires less energy compared to making them from raw materials.
- Supports the Economy: Recycling creates jobs in the recycling and manufacturing industries, boosting the economy.
In summary, recycling transforms old materials into new products, making it an essential practice for sustainable living. It helps protect the environment, conserve resources, and promotes a healthier planet for future generations.

Production of Bio Gas using Animals Excreta

Bio gas is a type of renewable energy source that is produced through the decomposition of organic matter in the absence of oxygen. It is primarily composed of methane gas (CH4) and carbon dioxide (CO2), along with small amounts of other gases such as hydrogen sulfide (H2S) and nitrogen (N2). Bio gas can be produced using various organic materials, including animals excreta.

Process of Bio Gas Production:

The production of bio gas using animals excreta involves the following steps:

1. Collection of Animals Excreta: The first step is to collect the excreta of animals such as cows, buffaloes, pigs, or poultry. These excreta contain organic matter such as dung and urine, which are rich in bacteria and other microorganisms.

2. Mixing with Water: The collected excreta are mixed with water to create a slurry. This slurry provides a suitable environment for the growth and activity of anaerobic bacteria, which are responsible for the fermentation process.

3. Anaerobic Fermentation: The slurry is then transferred to a bio gas digester, which is an airtight container or pit. The digester provides an oxygen-free environment necessary for anaerobic fermentation. Anaerobic bacteria present in the slurry break down the organic matter and produce bio gas as a byproduct.

4. Methane Production: During the fermentation process, the anaerobic bacteria convert the organic matter into simpler compounds such as methane (CH4) and carbon dioxide (CO2). Methane is the primary component of bio gas and is responsible for its combustible properties.

5. Storage and Utilization: The produced bio gas is stored in a separate chamber in the digester, where it can be collected and used as a source of energy. It can be used for cooking, heating, or generating electricity.

Advantages of Bio Gas Production using Animals Excreta:

- Renewable Energy: Bio gas is a renewable source of energy as it is produced from organic waste materials, which are continually generated.

- Waste Management: The use of animals excreta for bio gas production helps in managing and utilizing the organic waste effectively, reducing the environmental impact.

- Energy Independence: Bio gas production provides a decentralized source of energy, reducing dependency on fossil fuels and grid-based electricity.

- Reduced Emissions: The combustion of bio gas produces fewer greenhouse gas emissions compared to fossil fuels, contributing to reduced carbon footprint and mitigating climate change.

- Nutrient-Rich Residue: The leftover material after the fermentation process, known as bio slurry, is a nutrient-rich fertilizer that can be used in agriculture, improving soil fertility.

In conclusion, bio gas can be produced using animals excreta through a process of anaerobic fermentation. This sustainable energy source not only helps in waste management but also provides a renewable and environmentally friendly alternative to traditional forms of energy.

Understanding the Ingredients in Curry
When preparing curry, different ingredients can be added to enhance flavor and texture. In this scenario, the cook chose to add curd to the boiling curry. Here's why curd is often preferred:
1. Flavor Enhancement
- Curd adds a tangy flavor that complements the spices in curry.
- It balances out the heat from chili peppers, creating a well-rounded taste.
2. Creaminess
- Curd contributes a creamy texture, making the curry richer.
- It helps in thickening the curry, giving it a more luxurious mouthfeel.
3. Nutritional Benefits
- Curd is a source of probiotics, which are beneficial for digestion.
- It provides calcium and protein, adding nutritional value to the meal.
4. Cultural Relevance
- In many cuisines, especially Indian, curd is commonly added to curry.
- It is traditional to use curd in various recipes to enhance authenticity.
Why Not Milk, Cream, or Chocolate?
- Milk: While it can be used, it may not provide the same tanginess or thickness as curd.
- Cream: This ingredient adds richness but lacks the tangy flavor that curd offers.
- Chocolate: Adding chocolate would not be appropriate for a savory dish like curry, as it would overpower the other flavors.
In conclusion, curd was the ideal choice for the cook to add to the boiling curry, balancing flavors, enhancing texture, and providing nutritional benefits.

Understanding Biodegradable Waste
Biodegradable waste refers to organic materials that can decompose naturally through the action of microorganisms, such as bacteria and fungi. This type of waste is essential for maintaining a healthy environment.
Characteristics of Biodegradable Waste
- Natural Composition: Biodegradable waste consists of items such as food scraps, garden waste, paper, and other organic materials.
- Decomposition Process: These materials break down over time, returning nutrients to the soil, which helps improve soil fertility.
- Environmental Benefits: By decomposing, biodegradable waste helps reduce landfill accumulation and lowers greenhouse gas emissions.
Importance in Soil Health
- Nutrient Recycling: As biodegradable waste decomposes, it releases valuable nutrients back into the soil, fostering plant growth.
- Soil Structure Improvement: The addition of organic matter from decomposed waste enhances soil structure, leading to better water retention and aeration.
Conclusion
Choosing biodegradable waste management practices is crucial for sustainable living. By composting or recycling these materials, we contribute to a healthier ecosystem and promote a cleaner environment. This is why the correct answer to the question is option 'B'—biodegradable waste can easily decompose and mix with soil, making it beneficial for both our planet and agriculture.

The correct answer is option 'D' which means any one of net, chicken mess and wire mesh can be spread at the bottom of the pit dug to make a home for red worms. This is because red worms need a moist and organic substrate or bedding to live in where they can eat and convert it into castings. Moisture and organic matter are essential for a healthy habitat for the red worms. The pit dug should have a wire mesh at the bottom which will help keep the worms in and other pests out. Additionally, a net, chicken mess or any combination of these three can be used as bedding for the red worms. This will provide them with the nutrients they need to thrive.

Process of Waste Treatment - Sewage Treatment
The process of waste treatment, specifically for domestic and industrial wastewater, is commonly referred to as sewage treatment. Sewage treatment involves several steps to ensure that harmful contaminants are removed from the water before it is discharged back into the environment.

Key Steps in Sewage Treatment:
- Primary Treatment: In this initial stage, large solids are removed from the wastewater through physical processes like screening and sedimentation. This helps in reducing the overall organic load in the water.
- Secondary Treatment: This stage involves biological processes where microorganisms break down the organic matter present in the water. This step is crucial in reducing the levels of harmful pollutants.
- Tertiary Treatment: The final stage of sewage treatment involves further filtration and disinfection to remove any remaining impurities and pathogens. Methods like chlorination are often used to ensure that the treated water is safe for discharge.
- Reuse and Recycling: In some cases, the treated wastewater can be recycled for non-potable purposes like irrigation or industrial processes. This helps in conserving water resources and reducing the strain on freshwater sources.

Importance of Sewage Treatment:
- Protecting the Environment: Proper sewage treatment helps in preventing the contamination of water bodies like rivers and lakes, which can have detrimental effects on aquatic life and ecosystems.
- Public Health: By removing harmful pollutants and pathogens from wastewater, sewage treatment helps in safeguarding public health and preventing the spread of waterborne diseases.
- Sustainable Practices: Implementing effective sewage treatment practices promotes sustainable water management and ensures the long-term availability of clean water resources for future generations.