All questions of NCERT Based Tests for BPSC (Bihar) Exam

The Government of India instituted an ‘Amrita Devi Bishnoi National Award for Wildlife Conservation’ in the memory of Amrita Devi Bishnoi, who in 1731 sacrificed her life along with 363 others for the protection of ‘khejri’ trees in Khejarli village near Jodhpur in Rajasthan.

When 6 gram of carbon is 16 gram oxygen bicycle of carbon dioxide is produced if 6 gram of carbon is burn this gram of oxygen then the carbon dioxide used below answer

Introduction:
In the given options, we are asked to identify the natural polymers among cotton, PET, and plastic. To determine this, we need to understand what natural polymers are and how they differ from synthetic polymers.

Natural Polymers:
Natural polymers are large molecules composed of repeating subunits found in nature. These polymers are typically derived from living organisms and can be extracted or synthesized from natural sources. Unlike synthetic polymers, natural polymers have a complex molecular structure and are biodegradable.

Analysis of the Options:
Let's analyze each option to determine if it is a natural polymer:

1. Cotton: Cotton is a natural polymer. It is composed of cellulose, a complex carbohydrate, which is a natural polymer found in the cell walls of plants. Cotton fibers are made up of long chains of cellulose molecules, making it a natural polymer.

2. PET (Polyethylene terephthalate): PET is a synthetic polymer and not a natural polymer. It is a thermoplastic polymer that is derived from petroleum. PET is commonly used in the production of bottles, containers, and polyester fibers.

3. Plastic: The term "plastic" is a broad category that includes both natural and synthetic polymers. However, in the context of the given options, it is unclear which specific type of plastic is being referred to. Some plastics, such as polypropylene and polyethylene, are derived from petroleum and are synthetic polymers. On the other hand, there are certain types of natural polymers, such as natural rubber and shellac, that can be considered as plastics. Without further information, we cannot definitively categorize "plastic" as a natural polymer.

Conclusion:
Based on the analysis, it can be concluded that cotton (option 1) is the only example of a natural polymer among the given options. PET (option 2) is a synthetic polymer, and the categorization of "plastic" (option 3) as a natural polymer is ambiguous without additional information. Therefore, the correct answer is option 'A' - 1 only.

All the Biotic Components in an area together with the abiotic constituents of the environment form an ecosystem. Biotic components comprising living organisms and abiotic components comprising physical factors like temperature, rainfall, wind, soil and minerals

The correct answer is option 'D' - 1, 2 and 3. Let's understand why each statement is correct:

1. It enhances the water holding capacity of the soil:
Organic manure, such as compost or animal manure, contains organic matter that improves the water holding capacity of the soil. When organic matter decomposes, it forms humus, which acts as a sponge, holding water in the soil. This helps to prevent water runoff and allows the soil to retain moisture for a longer period. As a result, the soil becomes more capable of sustaining plant growth, especially during dry periods.

2. It makes the soil loose and porous:
Organic manure contains organic matter that enriches the soil and improves its structure. The organic matter helps to break up compacted soil, making it loose and porous. This improves the soil's ability to hold air and water, facilitating better root growth and nutrient uptake by plants. The increased porosity also enhances soil drainage, preventing waterlogging and reducing the risk of root rot.

3. It enhances the number of friendly microbes:
Organic manure provides a food source for beneficial microorganisms in the soil. These microbes break down organic matter and release essential nutrients in a form that plants can absorb. The presence of organic manure in the soil promotes the growth and multiplication of these beneficial microbes, such as bacteria, fungi, and earthworms. These microbes help in nutrient cycling, soil aeration, and the suppression of harmful pathogens, thus creating a healthier soil ecosystem.

In conclusion, organic manure has several positive effects on soil health. It enhances the water holding capacity of the soil, making it more resilient to drought conditions. It also improves soil structure, making it loose and porous, which aids in root growth and nutrient availability. Additionally, organic manure promotes the growth of friendly microbes that contribute to nutrient cycling and soil health. Therefore, all three statements are correct.

Red Sindhi is indigenous breed with higher yield than Sahiwal or Ongole.
jersey is exotic breed of France.
reference taken from www.agritech.tnau.ac.in

Vaccination doesn't kill polio causing microbes.
Also it cannot prevent the entry of polio causing viruses.
It only creates immunity against the virus.

Introduction:
Nitrogen is an essential nutrient required by plants for their growth and development. It is a major component of proteins, nucleic acids, and chlorophyll. Most plants obtain nitrogen from the soil in the form of nitrates or ammonium ions. However, some crops have the ability to fix atmospheric nitrogen with the help of symbiotic bacteria.

Explanation:
Among the given options, beans (option C) do not require nitrogenous fertilizer. Let's understand why.

Nitrogen Fixation:
Some plants have a symbiotic relationship with nitrogen-fixing bacteria, which are capable of converting atmospheric nitrogen into a usable form for plants. This process is called nitrogen fixation. These bacteria reside in root nodules of leguminous plants, such as beans, peas, and lentils. The bacteria take atmospheric nitrogen and convert it into ammonia, which is then used by the plants for their growth. Therefore, leguminous crops like beans do not require nitrogenous fertilizers as they can obtain nitrogen through biological fixation.

Other Crops:
1. Wheat (option A): Wheat is not capable of nitrogen fixation and relies on the availability of nitrogen in the soil. Therefore, wheat crops require nitrogenous fertilizers to meet their nitrogen requirements.
2. Millet (option B): Similar to wheat, millet crops do not have the ability to fix atmospheric nitrogen. Hence, they need nitrogenous fertilizers to fulfill their nitrogen needs.
3. Paddy (option D): Paddy, also known as rice, does not have the ability to fix nitrogen either. It requires nitrogenous fertilizers to meet its nitrogen demands.

Conclusion:
In conclusion, among the given options, beans do not require nitrogenous fertilizers as they have the ability to fix atmospheric nitrogen with the help of symbiotic bacteria present in their root nodules. On the other hand, crops like wheat, millet, and paddy rely on nitrogenous fertilizers to meet their nitrogen requirements.

Refraction of Sound: Explanation

Introduction:
Sound is a form of energy that travels in the form of waves through different mediums. The speed of sound varies depending on various factors such as temperature, humidity, and wind conditions. One of the phenomena that affect the propagation of sound is refraction.

Definition of Refraction:
Refraction is the bending of sound waves as they pass from one medium to another due to a change in their speed. When sound waves enter a medium with a different density or temperature, they change their direction.

Refraction of Sound in the Atmosphere:
During the day, the temperature of the Earth's surface increases, leading to the heating of the air closest to the surface. This causes the air near the surface to be less dense compared to the higher layers of the atmosphere. As a result, the speed of sound in the lower layers of the atmosphere is lower than the speed of sound in the upper layers.

Explanation:
The phenomenon of refraction causes sound waves to bend towards the region of higher speed as they travel from one medium to another. In the case of sound traveling through the atmosphere, the sound waves tend to bend away from the surface of the Earth during the day.

This bending of sound waves away from the surface of the Earth during the day prevents the sound from reaching longer distances. The sound waves get reflected back towards the ground due to the change in medium and the bending effect. Hence, the sound is heard at shorter distances during the day.

However, during the night, the surface of the Earth cools down, causing the air near the surface to become denser. This leads to a reversal in the density gradient of the atmosphere. As a result, the sound waves tend to bend towards the surface of the Earth during the night.

Implication:
This bending effect allows sound waves to travel longer distances during the night. The sound waves refract towards the ground and follow a curved path, allowing them to reach distant locations. This is why sound is heard at longer distances during the night compared to the day.

Conclusion:
In conclusion, the phenomenon of refraction plays a significant role in the propagation of sound waves. During the day, the bending of sound waves away from the surface of the Earth limits the distance over which the sound can be heard. However, during the night, the bending of sound waves towards the surface of the Earth allows them to travel longer distances, resulting in sound being heard at greater distances.

Rocket Propulsion follow these two principles: 

A physical change involves only change in physical state whereas a chemical change results in the formation of new substances. Boiling of water, melting of ice and dissolution of salt are physical changes as no new products are formed.

Differences between plant and animal cells:

1. Cell wall:
- Statement 1: Animal cells, in contrast to plant cells, do not have a cell wall.
- Explanation: The cell wall is a rigid structure that surrounds the cell membrane in plant cells. It provides support and protection to the cell. Animal cells, on the other hand, do not have a cell wall. Instead, they have a flexible cell membrane that allows for movement and flexibility.

2. Plastids:
- Statement 2: Plastids are found only in plant cells.
- Explanation: Plastids are specialized organelles found in plant cells. They are responsible for various functions, such as photosynthesis, storage of pigment, and synthesis of lipids. Plastids include chloroplasts (responsible for photosynthesis), chromoplasts (store pigments), and leucoplasts (store starch and oils). Animal cells do not possess plastids.

3. Vacuoles:
- Statement 3: Plant cells have one, central vacuole, whereas animal cells have many small vacuoles.
- Explanation: Vacuoles are fluid-filled sacs found in both plant and animal cells, but their size and number differ. Plant cells typically have one large central vacuole that occupies a significant portion of the cell's volume. This central vacuole serves various functions, including storage of water, ions, nutrients, and waste products. In contrast, animal cells have multiple small vacuoles that are scattered throughout the cytoplasm. These vacuoles are involved in diverse functions such as storage, digestion, and excretion.

Conclusion:
- Correct answer: Option C (2 and 3 Only)
- Explanation: The correct statements are 2 and 3. Animal cells lack a cell wall (statement 1 is incorrect). Plastids are exclusive to plant cells (statement 2 is correct). Plant cells have a central vacuole, while animal cells have multiple small vacuoles (statement 3 is correct).

**Explanation:**

When a positive charge moves in a magnetic field, it experiences a force perpendicular to both its velocity and the magnetic field direction. This force is given by the formula:

**F = q(v x B)**

Where:
- **F** is the force experienced by the charge
- **q** is the charge of the particle
- **v** is the velocity of the particle
- **B** is the magnetic field

In this case, the positive charge is moving towards a person, so its velocity is directed towards the person. The force experienced by the charge will be perpendicular to both the velocity and the magnetic field.

If the magnetic field lines were vertically upward or downward, the force experienced by the charge would be in the horizontal direction. This would cause the charge to move in a circular path around the person.

However, if the magnetic field lines were directed in a clockwise or anticlockwise direction, the force experienced by the charge would have a vertical component. This means that the charge would be pushed either upwards or downwards, depending on the direction of the magnetic field.

Since the positive charge is moving towards the person, the force experienced by the charge must be directed away from the person in order to push the charge towards them. This can only happen if the magnetic field lines are directed in the **anticlockwise** direction, as shown in the diagram below:

```
X → O
↑ ↑
| |
| |
↓ ↓
O ← X
```

Here, the X represents the positive charge, the O represents the person, and the arrows represent the direction of the magnetic field lines.

Therefore, the correct answer is option **B) Anticlockwise direction**.

Kinetic Energy and Velocity

Kinetic energy is the energy possessed by an object due to its motion. It is directly proportional to the mass of the object and the square of its velocity. The formula for kinetic energy is given by:

K.E. = (1/2)mv^2

Where:
K.E. = Kinetic energy
m = Mass of the body
v = Velocity of the body

Effect of Doubling Velocity

When the velocity of a body is doubled, it means that the new velocity becomes twice the initial velocity. Let's assume the initial velocity of the body is 'u' and the new velocity is '2u'.

Comparing the Initial and Final Kinetic Energies
To understand the effect of doubling velocity on kinetic energy, let's compare the initial and final kinetic energies.

Initial Kinetic Energy:
K.E. = (1/2)mu^2

Final Kinetic Energy:
K.E. = (1/2)m(2u)^2
K.E. = (1/2)m(4u^2)
K.E. = 2mu^2

Comparing the initial and final kinetic energies, we observe that the final kinetic energy is four times the initial kinetic energy. Therefore, when the velocity of a body is doubled, its kinetic energy becomes four times larger.

Explanation:
The increase in kinetic energy is due to the fact that kinetic energy is directly proportional to the square of the velocity. When the velocity is doubled, the new velocity is squared, resulting in a four-fold increase in kinetic energy. This relationship can be understood by considering the formula for kinetic energy, where the velocity is squared.

Conclusion:
The kinetic energy of a body becomes four times larger when its velocity is doubled. This increase in kinetic energy is due to the direct relationship between kinetic energy and the square of velocity.

Its an exothermic process.

Explanation:

Statement 1: Calcium hydroxide is also called as quicklime.
- This statement is incorrect. Calcium hydroxide is not the same as quicklime. Quicklime is actually calcium oxide (CaO), which is produced by heating calcium carbonate (lime) at high temperatures.

Statement 2: Calcium hydroxide reacts slowly with the carbon dioxide in air to form a thin layer of calcium carbonate on the walls after two to three days of whitewashing.
- This statement is correct. When calcium hydroxide (also known as slaked lime) is exposed to the carbon dioxide in the air, it reacts to form calcium carbonate. This process, known as carbonation, results in the formation of a thin layer of calcium carbonate on the walls after a few days of whitewashing.

Therefore, the correct answer is option B - 2 Only.

The correct answer is option 'B', the Ramsar Convention.

The Ramsar Convention is an international treaty that was signed in Ramsar, Iran, in 1971. It is officially called the Convention on Wetlands of International Importance, especially as Waterfowl Habitat. This convention is dedicated to the conservation and wise use of wetlands, recognizing their ecological importance and the vital role they play in maintaining biodiversity and providing various ecosystem services.

The Ramsar Convention aims to achieve the following objectives:

1. Conservation: The convention promotes the conservation and wise use of wetlands, recognizing their importance for maintaining ecological processes, biodiversity, and the overall health of the planet. It encourages the establishment of protected areas and the implementation of management plans to ensure the long-term conservation of wetland habitats.

2. International Cooperation: The Ramsar Convention facilitates international cooperation among member countries for the conservation and sustainable use of wetlands. It encourages the exchange of scientific knowledge, technical expertise, and information related to wetland conservation.

3. Identification and Designation of Wetlands of International Importance: The convention provides a framework for identifying and designating wetlands of international importance, also known as Ramsar sites. These sites are recognized for their significant ecological, botanical, zoological, limnological, or hydrological value. There are currently over 2,400 Ramsar sites around the world, covering a total area of over 250 million hectares.

4. Wise Use of Wetlands: The Ramsar Convention emphasizes the wise use of wetlands, taking into account the ecological, social, cultural, and economic aspects. It promotes sustainable development practices that maintain the ecological character of wetlands while providing benefits to local communities.

5. Public Awareness and Education: The convention encourages public awareness and education about the importance of wetlands and the need for their conservation. It promotes the involvement of local communities, indigenous peoples, and other stakeholders in wetland management and decision-making processes.

In conclusion, the Ramsar Convention is the international treaty that specifically protects wetlands on a global basis. It aims to conserve and sustainably manage wetlands, recognizing their ecological importance and the need for international cooperation in their conservation efforts.

Cod liver oil is obtained from fishes. It is abundant in vitamin A and D. It is also rich in other nutrients.

The smallest unit of power is the watt (W). Let's understand why the watt is considered the smallest unit of power.

The definition of power is the rate at which work is done or energy is transferred. It is the measure of how quickly or slowly a certain amount of work is done or energy is used. In other words, power tells us how fast or slow something is happening.

The watt is named after James Watt, an 18th-century Scottish engineer who made significant contributions to the development of the steam engine. He is known for inventing the horsepower unit of power, but the watt is a smaller unit and is widely used in the International System of Units (SI).

Power can be calculated by dividing the amount of work done by the time it takes to do that work. Mathematically, power (P) is equal to work (W) divided by time (t). Therefore, the unit of power is derived from the units of work and time.

Here's why the other options are not the smallest unit of power:

b) Kilowatt (kW): A kilowatt is equal to 1000 watts. It is a larger unit of power commonly used in electrical systems or to measure the power output of engines or appliances.

c) Horsepower (hp): Horsepower is a unit of power that was originally derived by James Watt to compare the power output of steam engines to that of horses. One horsepower is equal to approximately 745.7 watts. While it is widely used in the automotive and engineering industries, it is not the smallest unit of power.

d) Milliwatt (mW): A milliwatt is equal to one thousandth (1/1000) of a watt. It is a smaller unit of power commonly used in electronics, telecommunications, and other low-power applications. However, the watt is still smaller than the milliwatt and is considered the smallest unit of power.

In conclusion, the watt is the smallest unit of power as it is the base unit in the SI system. It is derived from the fundamental units of work and time, making it the most commonly used unit for measuring power.

The sensation of a sound perceived in an ear is measured by another term called loudness which depends on intensity of sound and sensitiveness of the ear. Unit of loudness is bel. A practical unit of loudness is decibel (dB) which is 1/10th of bel. Another unit of loudness is phon.

Cornea Transplant in Eye Donation
The part of the eyes that is typically transplanted during eye donation is the cornea.

Cornea
- The cornea is the clear, dome-shaped surface that covers the front of the eye. It plays a crucial role in focusing light entering the eye.
- When the cornea becomes damaged or diseased, it can lead to vision problems, such as blurry vision or discomfort.
- A cornea transplant, also known as keratoplasty, involves replacing a damaged or diseased cornea with a healthy cornea from a donor.

Eye Donation Process
- Eye donation involves donating the cornea of a deceased person to help improve the vision of someone in need.
- The process of eye donation is typically done shortly after death, and it is important for the cornea to be retrieved within a few hours to ensure its viability for transplantation.
- Eye donation is a selfless act that can provide the gift of sight to those who are visually impaired.

Importance of Cornea Transplant
- Cornea transplants are often performed to improve vision or alleviate discomfort caused by various corneal conditions.
- It can help restore vision in individuals with corneal scarring, keratoconus, or other corneal diseases.
- By donating corneas, individuals can make a significant impact on the lives of others by giving them the gift of sight.

We can see the objects only when light falls on the object, and is then reflected to the eyes.

Explanation:

Assertion A: Utensils used to store food have a layer of tin electroplated over iron.
- This statement is correct. Utensils such as cans used for storing food often have a layer of tin electroplated over iron to prevent the iron from corroding and reacting with the food.

Reasoning R: Tin is less reactive than iron.
- This statement is also correct. Tin is less reactive than iron, which makes it a suitable material for coating iron utensils. The tin layer acts as a barrier between the iron and the food, preventing any chemical reactions that could potentially contaminate the food.
Therefore, both Assertion A and Reasoning R are correct, and Reasoning R is the correct explanation for Assertion A. Tin's lower reactivity compared to iron makes it an ideal choice for electroplating over iron utensils used for storing food, as it helps ensure the safety and quality of the stored food.

Plant Cell vs Animal Cell: Difference in Cell Walls

The correct answer to the given question is option 'A', which states that plant cells have cell walls while animal cells do not. Let us explore this difference in detail.

1. Plant Cell:
- Cell Wall: One of the key features of a plant cell is the presence of a rigid cell wall surrounding the cell membrane. The cell wall is made up of cellulose and provides structural support and protection to the cell.
- Cell Membrane: Plant cells also have a cell membrane, which is a selectively permeable barrier that controls the movement of substances in and out of the cell.
- Vacuole: Plant cells typically have a large central vacuole that helps maintain the cell's shape, stores water, nutrients, and waste products, and contributes to cell expansion and growth.
- Plastids: Plant cells contain various types of plastids, including chloroplasts (which carry out photosynthesis), chromoplasts (responsible for pigment synthesis), and leucoplasts (involved in storage of starch, oils, and proteins).

2. Animal Cell:
- Cell Membrane: Similar to plant cells, animal cells also have a cell membrane that regulates the movement of substances into and out of the cell.
- No Cell Wall: Unlike plant cells, animal cells lack a cell wall. Instead, they have a flexible and elastic cell membrane that allows them to change shape.
- No Central Vacuole: Animal cells may contain small vacuoles, but they are not as prominent or centrally located as in plant cells.
- Fewer Plastids: Animal cells generally have very few or no plastids. They do not possess chloroplasts and are unable to carry out photosynthesis.

Significance of Cell Walls in Plant Cells:
The presence of a cell wall in plant cells serves several important functions:
- It provides structural support and rigidity to the cell, allowing plants to maintain their shape even in the absence of external support.
- The cell wall acts as a barrier against mechanical stress and protects the cell from damage.
- It helps prevent excessive water uptake and maintains the osmotic balance of the cell.
- The cell wall contributes to the transport of water and nutrients through specialized structures called plasmodesmata.

In conclusion, the key difference between plant cells and animal cells lies in the presence of a cell wall, which is unique to plant cells. This cell wall provides structural support, protection, and several other functions that are essential for the survival and functioning of plants.

The correct answer is option 'D', neither 1 nor 2. Let's understand why this is the correct answer by analyzing each statement:

1. A female gamete is smaller than a male gamete and likely to be motile.
This statement is incorrect. In most organisms, including humans, the female gamete, which is the egg or ovum, is larger than the male gamete, which is the sperm. The egg is a non-motile gamete and does not have the ability to move on its own. It is usually stationary and waits to be fertilized by a sperm.

2. Male gametes are large and contain food-stores.
This statement is also incorrect. Male gametes, or sperm, are actually much smaller than female gametes. Sperm are highly specialized cells that are adapted for swimming to reach and fertilize the egg. They are streamlined and have a flagellum, or tail, which allows them to move. Sperm do not contain food-stores. Instead, they are equipped with mitochondria that provide energy for their movement.

Explanation:
It is important to understand the basic differences between male and female gametes. Gametes are reproductive cells that fuse during fertilization to form a new individual. In most organisms, including humans, the male gamete is called sperm and the female gamete is called the egg or ovum.

- Size and Motility:
- The female gamete, or egg, is much larger in size compared to the male gamete, sperm.
- The egg is non-motile and does not possess the ability to move on its own.
- On the other hand, sperm are much smaller in size and possess a flagellum that allows them to swim and reach the egg for fertilization.

- Nutrient Stores:
- The statement that male gametes contain food-stores is incorrect.
- Sperm do not contain food-stores but are equipped with mitochondria that provide energy for their movement.
- The female gamete, or egg, contains nutrient stores in the form of yolk, which provides nourishment for the developing embryo.

- Fertilization:
- During fertilization, a sperm penetrates the egg and fuses with it to form a zygote, which eventually develops into an embryo.
- The egg provides the necessary nutrients for the initial stages of development until the embryo can establish its own nutrient supply.

Conclusion:
In summary, the correct answer is option 'D', as both statements given in the question are incorrect. The female gamete is larger than the male gamete and is non-motile, while male gametes, or sperm, are smaller, motile, and do not contain food-stores.

The correct answer is option 'C' - Newton.

Newton is the SI unit of force. It is named after Sir Isaac Newton, a renowned physicist who made significant contributions to the field of mechanics. Newton's laws of motion form the foundation of classical physics, and the unit of force was named in his honor.

Here's a detailed explanation of why the SI unit of force is Newton:

1. Definition of Force:
- Force is defined as an external agent that can change the state of motion or shape of an object.
- It is a vector quantity, which means it has both magnitude and direction.

2. Newton's Second Law of Motion:
- Newton's second law of motion states that the force acting on an object is directly proportional to the rate of change of its momentum.
- Mathematically, F = ma, where F is the force, m is the mass of the object, and a is its acceleration.
- This equation shows that force is equal to the product of mass and acceleration.

3. SI Unit of Mass and Acceleration:
- The SI unit of mass is kilogram (kg). It is the base unit for mass in the International System of Units.
- The SI unit of acceleration is meter per second squared (m/s²). It is the rate of change of velocity per unit time.

4. SI Unit of Force:
- By substituting the SI units of mass (kg) and acceleration (m/s²) into Newton's second law of motion equation (F = ma), we get the SI unit of force as kg * m/s².
- This unit is known as Newton (N).

Therefore, the SI unit of force is Newton (N), which is equivalent to kg * m/s². It represents the amount of force required to accelerate a 1 kg mass by 1 meter per second squared.

In conclusion, the SI unit of force is Newton (N), and it is derived from Newton's second law of motion, which relates force, mass, and acceleration.

Respiration in Plants

Plants undergo respiration just like animals do. During respiration, plants take in air through small pores called stomata present on their leaves. The air contains oxygen and carbon dioxide. The process of respiration occurs in two stages:

1. Glycolysis - In this stage, glucose is broken down into pyruvate molecules. This process occurs in the cytoplasm of the plant cell and does not require oxygen.

2. Aerobic Respiration - In this stage, the pyruvate molecules produced in glycolysis are further broken down in the presence of oxygen. This process occurs in the mitochondria of the plant cell.

What Happens Next?

After taking in air during respiration, the plants utilize oxygen and give out carbon dioxide into the atmosphere. This is because during the second stage of respiration, the pyruvate molecules combine with oxygen to produce carbon dioxide, water, and energy.

The equation for respiration in plants is:

Glucose + Oxygen → Carbon Dioxide + Water + Energy

Therefore, the correct answer to the given question is option B, i.e., plants utilize oxygen and give out carbon dioxide during respiration.

The correct answer is option 'C' - 1, 3, and 5 only.

Explanation:
1. Arsenic: Arsenic contamination in drinking water is a major issue in many parts of India, particularly in the states of West Bengal, Bihar, Uttar Pradesh, and Assam. High levels of arsenic can cause various health issues, including skin problems, cancer, and organ damage.

2. Sorbitol: Sorbitol is a sugar alcohol commonly used as a sweetener in food and pharmaceutical products. It is not typically found as a pollutant in drinking water.

3. Fluoride: Fluoride contamination in drinking water is another significant problem in India, especially in states like Rajasthan, Gujarat, and Andhra Pradesh. High levels of fluoride can lead to dental and skeletal fluorosis, which cause severe damage to teeth and bones.

4. Formaldehyde: Formaldehyde is a colorless gas with a strong odor. It is not commonly found as a pollutant in drinking water in India.

5. Uranium: Uranium contamination in drinking water is a growing concern in several parts of India, including the states of Punjab, Rajasthan, and Jharkhand. High levels of uranium can have harmful effects on the kidneys and other organs.

Overall, the correct answer is option 'C' as both arsenic and fluoride are well-known pollutants in drinking water in some parts of India, while sorbitol, formaldehyde, and uranium are not commonly found contaminants.

According to Newton's second law, The rate of change of linear momentum of a body is directly proportional to the external force applied on the body , and takes place always in the direction of the force applied. So the rate of change of momentum is Force i.e. Newton's second law helps us to derive an equation for force.

Because the helium atoms are of lower mass than the average is molecules, the helium gas is less dense than air. The balloon thus weighs less than the air displaces by its volume.

Rabbi is a Hebrew term that means "my teacher" or "my master." It is a title given to Jewish religious leaders who have been ordained and have received extensive education in Jewish law, ethics, and traditions. Rabbis are responsible for interpreting religious texts, providing guidance to their communities, and leading religious services.

Alternative Name
The other name for rabbis is Hydrophobia. However, it is important to note that this answer is incorrect. The term "hydrophobia" does not have any connection to rabbis or their role in Judaism.

Explanation
The term "hydrophobia" is often used to refer to a symptom of rabies, a viral disease that affects the central nervous system of mammals. Rabies is typically transmitted through the bite or scratch of an infected animal. Symptoms of rabies include fever, headache, muscle aches, excessive salivation, and fear of water (hydrophobia). This fear of water is due to the difficulty in swallowing caused by the virus affecting the throat muscles.

Correct Answer
The correct answer to the question is not "hydrophobia." It is important to carefully read the options provided and select the correct answer, which is often based on knowledge and understanding of the topic being asked. In this case, the correct answer is not provided among the options given, as none of the options are alternative names for rabbis.

Heat flows from a body of higher temperature to a body of lower temperature. Here the temperature of both the objects is the same. So, heat will not flow from one object to another or there will not be any change in the temperature of both the two objects.

Adaptations of the Frog Differentiating it from the Fish

Introduction:
The frog belongs to the class Amphibia, while fish belong to the class Pisces. Although both frogs and fish are adapted to live in aquatic environments, there are certain adaptations that differentiate frogs from fish. One such adaptation is the ability of frogs to live in water as well as on land.

Ability to Live in Water and on Land:
Frogs possess the ability to live both in water and on land, whereas fish are exclusively aquatic organisms. This adaptation allows frogs to explore terrestrial habitats and exploit the resources available on land. Fish, on the other hand, lack limbs and other specialized structures required for movement on land.

Laying Eggs in Water:
Both frogs and fish lay eggs, but their modes of reproduction differ. Frogs lay their eggs in water, while fish lay their eggs in water as well. However, fish primarily reproduce through external fertilization, where the female releases eggs and the male simultaneously releases sperm over them. Frogs, on the other hand, undergo internal fertilization, where the male fertilizes the eggs inside the female's body before they are laid in water.

Streamlined Body:
Both frogs and fish possess streamlined bodies, but there are slight differences in their body shapes. Fish generally have a more streamlined body shape compared to frogs. This adaptation allows fish to move efficiently through water by reducing drag. Frogs, although not as streamlined as fish, have adapted to their semi-aquatic lifestyle by developing a body shape that enables them to move both in water and on land.

Presence of Mucous Glands in the Skin:
Frogs have mucous glands in their skin, while fish do not possess these specialized glands. These glands secrete a slimy substance called mucous, which helps frogs maintain their skin moist and protected. This adaptation is particularly important for frogs as they can easily dehydrate on land. Fish, on the other hand, have scales that provide protection against dehydration.

Conclusion:
In conclusion, the ability of frogs to live in both aquatic and terrestrial environments, along with their mode of reproduction, streamlined body shape, and presence of mucous glands in the skin, are adaptations that differentiate them from fish. These adaptations allow frogs to thrive in a variety of habitats and exploit resources both in water and on land.

Some of the most common properties of Aluminium are good thermal conductivity, malleability, light weight and high melting point which make it useful for making cooking utensils.

Tissues and Division of Labour in Multicellular Organisms

Tissues are groups of similar cells that work together to perform a specific function in the body. They are the building blocks of organs and are essential for the proper functioning of multicellular organisms. The presence of tissues in a multicellular organism ensures division of labour, which is the allocation of specific tasks to different groups of cells or tissues within the organism.

Division of Labour
- In a multicellular organism, different tissues are specialized to perform specific functions. This division of labour allows for more efficient functioning and higher overall productivity.
- Each tissue is specialized to carry out a particular function, such as protection, support, movement, or secretion.
- For example, muscle tissue is specialized for contraction and movement, while epithelial tissue is specialized for protection and secretion.
- This specialization allows the organism to perform complex tasks that would not be possible if all cells were identical and performed the same function.

Advantages of Division of Labour
- Increased Efficiency: Division of labour allows different tissues to focus on specific tasks, leading to increased efficiency in performing those tasks. Each tissue can develop specific adaptations and structures that enhance its function.
- Specialization: Different tissues can specialize in specific functions, which allows for the development of more complex and sophisticated organs and systems.
- Energy Conservation: Division of labour allows cells to specialize in certain functions, reducing the energy required for each cell to perform multiple tasks.
- Adaptability: The presence of specialized tissues allows multicellular organisms to adapt to different environments and perform a wide range of functions to ensure survival and reproduction.

Conclusion
The presence of tissues in a multicellular organism ensures division of labour, which is crucial for efficient functioning, specialization, energy conservation, and adaptability. By dividing tasks among different tissues, organisms can perform complex functions and enhance their overall fitness and survival.

Explanation:

The correct answer is option B: It will spread the force of the bag over the large area of the shoulder of the child producing less pressure.

Reasoning:

When designing school bags, it is important to consider the well-being and comfort of the students who will be carrying them. Broad strips on school bags serve a specific purpose, which is to distribute the force exerted by the bag over a larger surface area of the shoulder. This helps in reducing the pressure exerted on the shoulder and provides a more comfortable carrying experience for the child.

Advantages of Broad Strips:

1. Force Distribution: Broad strips on school bags help in spreading the force exerted by the bag over a larger area of the shoulder. This means that the weight of the bag is distributed more evenly, reducing the pressure on a specific point on the shoulder. This is especially important when students have to carry heavy books and other items in their bags.

2. Less Pressure: By distributing the force over a larger area, the pressure exerted on the shoulder is reduced. This can help prevent shoulder pain, discomfort, and even potential injuries that may arise from carrying heavy bags with narrow straps.

3. Improved Comfort: The use of broad straps on school bags enhances the overall comfort of carrying the bag. The broader straps provide better support and stability to the bag, allowing the child to carry it with ease for extended periods of time.

4. Prevention of Shoulder Strain: Carrying heavy bags with narrow straps can lead to strain on the shoulders, neck, and back. Broad straps help in minimizing this strain by evenly distributing the weight, reducing the risk of musculoskeletal issues.

5. Longevity of the Bag: By spreading the force over a larger area, the pressure on the straps themselves is reduced. This helps in preventing wear and tear on the straps, increasing the overall durability and longevity of the bag.

In conclusion, the provision of broad strips on school bags is beneficial as it spreads the force of the bag over a larger area of the shoulder, resulting in less pressure and improved comfort for the child.