Olympiad Test : General Science - 2 - Class 5 MCQ

Odd One Out:

A: Scurvy

B: Rickets

C: Malaria

D: Osteomalacia

Let's analyze each option to identify the odd one out:

Scurvy:

• Scurvy is a disease caused by a deficiency of vitamin C.


• It primarily affects the connective tissues and results in symptoms such as fatigue, joint pain, and bleeding gums.

Rickets:

• Rickets is a condition caused by a deficiency of vitamin D, calcium, or phosphate.


• It leads to weak and soft bones, growth retardation, and skeletal deformities in children.

Malaria:

• Malaria is a vector-borne infectious disease caused by the Plasmodium parasite.


• It is transmitted through the bite of infected mosquitoes.


• Malaria affects the red blood cells and can cause symptoms such as fever, headache, and fatigue.

Osteomalacia:

• Osteomalacia is a condition characterized by the softening of the bones due to a deficiency of vitamin D or problems with its metabolism.


• It can result in bone pain, muscle weakness, and an increased risk of fractures.

Based on the analysis:

• Scurvy, Rickets, and Osteomalacia are all conditions caused by nutritional deficiencies.


• Malaria, on the other hand, is an infectious disease caused by a parasite.

Conclusion:

The odd one out is C: Malaria as it is the only option that is not caused by a nutritional deficiency.

Spread by Rat Flea: Plague
The correct answer is D: Plague. The disease known as the plague is spread by an insect called the rat flea. Here is a detailed explanation:
What is the Plague?
The plague is a highly infectious and often deadly disease caused by the bacterium Yersinia pestis. It primarily affects small mammals such as rodents and can be transmitted to humans through the bite of infected fleas.
The Role of Rat Fleas:
Rat fleas are the main carriers of the Yersinia pestis bacteria. They typically infest rodents, particularly rats, which act as reservoirs for the disease. When an infected rat dies, the fleas move on to find new hosts, including humans, and transmit the bacteria through their bites.
Transmission to Humans:
When a rat flea carrying the Yersinia pestis bacteria bites a human, it can inject the bacteria into the bloodstream. Additionally, the bacteria can also enter the body through open wounds or inhalation of respiratory droplets from infected individuals.
Symptoms and Effects:
The plague can manifest in different forms, including bubonic, septicemic, and pneumonic. Bubonic plague is characterized by swollen lymph nodes (buboes), septicemic plague affects the bloodstream, and pneumonic plague affects the lungs. Common symptoms include fever, chills, weakness, and swollen lymph nodes.
Historical Significance:
The plague has had a significant impact on human history. The most well-known pandemic was the Black Death, which occurred during the 14th century and resulted in the deaths of millions of people across Europe and Asia. The disease is now rare, thanks to advancements in healthcare and sanitation practices.
In conclusion, the disease spread by the rat flea is the plague, caused by the bacterium Yersinia pestis. Rat fleas act as vectors and transmit the bacteria to humans through their bites. The plague has had a significant historical impact and is known for its devastating effects.

Answer:
The vaccination is not available for the following:
Common cold
- There is no vaccine available for the common cold.
- The common cold is caused by a variety of viruses, making it difficult to develop a single vaccine.
Tetanus
- There is a vaccine available for tetanus.
- The tetanus vaccine is recommended for people of all ages to protect against the bacteria that causes tetanus.
Polio
- There is a vaccine available for polio.
- The polio vaccine is part of routine immunization schedules and has helped to greatly reduce the incidence of polio worldwide.
Tuberculosis
- There is a vaccine available for tuberculosis, but it is not widely used.
- The Bacillus Calmette-Guérin (BCG) vaccine can help prevent severe forms of tuberculosis in children, but it is not as effective in preventing the transmission of the disease.
In conclusion, the vaccination is not available for the common cold (option A). Vaccines are available for tetanus, polio, and tuberculosis.

BCG vaccine is given to control:

• Tuberculosis (TB): BCG vaccine is primarily given to control tuberculosis, which is caused by the bacteria Mycobacterium tuberculosis. It is a highly contagious respiratory disease that affects the lungs and can spread to other parts of the body.

Explanation:

The BCG vaccine, which stands for Bacillus Calmette-Guérin, is a live attenuated vaccine derived from a strain of Mycobacterium bovis, a bacteria closely related to Mycobacterium tuberculosis. The vaccine is typically administered to infants and children in countries with a high incidence of tuberculosis.

Here is a breakdown of why BCG vaccine is given to control tuberculosis:

• Preventive measure: The BCG vaccine serves as a preventive measure against tuberculosis. It stimulates the immune system to recognize and fight the bacteria that cause TB.


• Reducing the risk of severe forms: BCG vaccination can reduce the risk of severe forms of tuberculosis, such as meningitis and disseminated TB, in children.


• Protection against complications: BCG vaccination helps protect against the complications of tuberculosis, such as tuberculosis meningitis, which can lead to brain damage or death.


• Reducing transmission: By reducing the prevalence of tuberculosis in the population, BCG vaccination can help decrease the transmission of the disease from person to person.


• Effectiveness: While the BCG vaccine is not 100% effective in preventing tuberculosis, it has been shown to be effective in reducing the risk of severe forms of the disease, especially in children.

It is important to note that the BCG vaccine does not provide lifelong immunity against tuberculosis, and its effectiveness may vary depending on factors such as the strain of the bacteria and the individual's immune response. Therefore, other measures such as early detection, proper treatment, and infection control practices are also crucial in controlling the spread of tuberculosis.

Pneumonia is caused by:
There are different causes of pneumonia, but the most common cause is bacterial infection. Here are the details:
Bacterial Infection:
- Pneumonia is often caused by bacteria, such as Streptococcus pneumoniae or Haemophilus influenzae.
- These bacteria can enter the lungs and cause inflammation and infection in the air sacs.
- Bacterial pneumonia can be severe and may require medical treatment with antibiotics.
Other Causes of Pneumonia:
- Viral Infection: Pneumonia can also be caused by viruses, such as influenza or respiratory syncytial virus (RSV).
- Fungal Infection: In some cases, fungi can cause pneumonia, especially in individuals with weakened immune systems.
- Aspiration: Inhalation of food, liquid, or vomit can lead to aspiration pneumonia, where the lungs become infected.
- Other Factors: Pneumonia can also be caused by other factors such as exposure to certain chemicals, toxins, or irritants.
Prevention and Treatment:
- Vaccination: Vaccines are available to protect against common causes of bacterial and viral pneumonia.
- Antibiotics: Bacterial pneumonia can be treated with antibiotics prescribed by a healthcare professional.
- Good Hygiene: Practicing good hand hygiene and avoiding close contact with individuals who have respiratory infections can help prevent the spread of pneumonia.
- Healthy Lifestyle: Maintaining a healthy lifestyle, including regular exercise, a balanced diet, and adequate rest, can help strengthen the immune system and reduce the risk of pneumonia.
Remember, it is important to consult a healthcare professional for a proper diagnosis and treatment plan if you suspect you have pneumonia.

Explanation:
When the temperature of a fixed amount of gas at constant volume decreases, its pressure decreases. This can be explained by the ideal gas law, which states that the pressure of a gas is directly proportional to its temperature.
Key Points:
- According to the ideal gas law, the pressure of a gas is directly proportional to its temperature.
- When the temperature of a gas decreases, the particles in the gas slow down and have less kinetic energy.
- With less kinetic energy, the particles collide with the container walls less frequently and with less force.
- As a result, the pressure exerted by the gas on the container decreases.
- This relationship between temperature and pressure is known as Charles's Law, which states that at constant volume, the pressure of a gas is directly proportional to its temperature.
Conclusion:
In summary, the pressure of a fixed amount of gas at constant volume decreases as its temperature decreases. This can be explained by the decrease in kinetic energy and frequency of collisions between gas particles and the container walls.

Explanation:
When the volume of a fixed amount of gas at constant temperature decreases, its pressure increases. This relationship is described by Boyle's Law, which states that the pressure of a gas is inversely proportional to its volume at constant temperature.
Here's a detailed explanation:
- Boyle's Law: Boyle's Law states that the pressure and volume of a gas are inversely proportional at constant temperature. Mathematically, it can be expressed as:
- P1V1 = P2V2
- P1 and V1 represent the initial pressure and volume, while P2 and V2 represent the final pressure and volume.
- In the given scenario, the volume of the gas is decreasing while the temperature remains constant. Therefore, we can apply Boyle's Law to determine the effect on pressure:
- When the volume decreases (V2 < V1), according to Boyle's Law, the pressure must increase (P2 > P1) to maintain the constant temperature.
- This can be explained by considering the gas particles. As the volume decreases, the same number of gas particles are confined to a smaller space. This leads to more frequent collisions between the particles and the walls of the container, resulting in an increase in pressure.
- Therefore, the correct answer is option A: Increases.

Explanation:
Water vapor condenses when it hits the ice surface
- When water vapor in the air comes into contact with the cold surface of the ice cubes, it loses heat and energy.
- This causes the water vapor molecules to slow down and come together, forming tiny liquid water droplets.
- These liquid droplets are what we see as mist or fog around the ice cubes.
Reasons why water vapor condenses on the ice surface:
- The temperature of the ice cubes is lower than the dew point temperature of the surrounding air.
- The dew point temperature is the temperature at which the air becomes saturated and cannot hold any more water vapor.
- When the air comes into contact with the cold surface of the ice cubes, its temperature drops below the dew point temperature, causing the water vapor to condense.
Other possible reasons:
- Water molecules in the ice vaporize: This is not the probable reason because ice cubes do not vaporize water molecules. Instead, they absorb heat from their surroundings.
- The ice cools the air around it and thus producing a visible convection current: While the ice cubes do cool the air around them, this does not directly produce mist. Mist forms when water vapor condenses, not due to convection currents.
- The air molecule gets cold and becomes denser around ice cubes: While the air around the ice cubes does get colder, this does not directly result in the formation of mist. Mist forms when water vapor condenses, not due to changes in air density.

The state of matter that has particles able to slide past each other, yet still packed together is Liquids.
Explanation:
- Liquids are one of the three main states of matter, along with solids and gases.
- In a liquid, the particles are close together and have a definite volume, similar to solids.
- However, unlike solids, the particles in a liquid are able to move past each other, allowing the liquid to flow and take the shape of its container.
- The particles in a liquid are not as tightly packed as in a solid, but they are still packed closely enough to maintain a fixed volume.
- This ability of particles to slide past each other while remaining packed together is what distinguishes liquids from solids and gases.
- In a solid, the particles are tightly packed and cannot move past each other, while in a gas, the particles are spread out and move freely.
- Examples of liquids include water, oil, and alcohol.
- Liquids play a vital role in various aspects of our daily lives, such as in cooking, cleaning, and transportation.

Answer:
The most common state of matter in the universe is called plasma. Here is a detailed explanation:
1. Introduction:
- The universe is composed of various types of matter, including solids, liquids, gases, and plasmas.
- However, the most abundant state of matter in the universe is plasma.
2. Definition of Plasma:
- Plasma is often referred to as the fourth state of matter.
- It is a highly ionized gas consisting of positively charged ions and negatively charged electrons.
- Plasma is characterized by its ability to conduct electricity and respond to magnetic fields.
3. Occurrence of Plasma:
- Plasma is found in various celestial objects, such as stars, including our own Sun.
- It also exists in interstellar space, where it forms nebulae and other astronomical phenomena.
- Additionally, plasma is present in lightning, auroras, and some man-made devices like fluorescent lights and plasma TVs.
4. Abundance of Plasma:
- The majority of the visible matter in the universe is in the form of plasma.
- It is estimated that more than 99% of the observable universe is composed of plasma.
- This is due to the fact that stars, which are predominantly composed of plasma, are extremely abundant in the universe.
5. Importance of Plasma:
- Plasma plays a crucial role in the dynamics and evolution of the universe.
- It is responsible for the generation of energy and heat in stars through nuclear fusion reactions.
- Plasma also contributes to the formation of galaxies, the interstellar medium, and the overall structure of the universe.
In conclusion, the most common state of matter in the universe is plasma. It is highly abundant, found in stars, interstellar space, and various other celestial phenomena. Plasma is a unique state of matter with distinct properties and plays a vital role in the dynamics of the universe.

Explanation:
Energy is a fundamental concept in physics and is closely related to the concept of work. Let's break down each statement to understand why option D is the correct answer.
A: Energy is the ability to do work and is used in order to perform work:
- Energy is defined as the capacity or ability to do work. It is required to perform any kind of work.
- Work, on the other hand, is the transfer of energy from one system to another or the change in energy of a system.
B: Energy is the rate at which work is done:
- This statement is not entirely accurate. Energy is not the rate at which work is done, but rather the ability or capacity to do work.
- However, work is indeed related to energy, as it is the transfer of energy or the change in energy of a system.
C: There are various units of energy, work, and energy:
- This statement is true. Energy, work, and power (which is the rate at which work is done) have different units of measurement.
- Energy can be measured in joules (J), work is also measured in joules (J), and power is measured in watts (W).
D: All of the above:
- This option is the correct answer because all three statements (A, B, and C) are true.
- Energy is the ability to do work, work is related to energy, and there are various units of measurement for energy, work, and power.
In conclusion, the correct statement is option D: All of the above.

Definition of ENERGY:

Energy can be defined as the capacity or ability to do work or make something happen. It is a fundamental concept in physics and is a measure of the ability of a system to perform tasks or cause changes in its surroundings.
Key Points:
- Energy is a fundamental concept in physics.
- It is the capacity or ability to do work or make something happen.
- It is a measure of the ability of a system to perform tasks or cause changes in its surroundings.
- Energy can exist in different forms, such as kinetic energy (energy of motion), potential energy (stored energy), thermal energy (heat), electrical energy, etc.
- The SI unit of energy is joule (J).
- Energy can neither be created nor destroyed, but it can be transformed from one form to another (law of conservation of energy).
Examples:
- When a person lifts a heavy object, energy is transferred from the person's muscles to the object, giving it potential energy.
- When a car is in motion, it possesses kinetic energy.
- When a light bulb is turned on, electrical energy is transformed into light energy.
Conclusion:
Energy is the capacity or ability to do work or make something happen. It exists in various forms and can be transformed from one form to another. Understanding the concept of energy is essential in understanding the physical world and its interactions.

Musical instruments and traffic on road are examples of sound energy.
Sound energy is a type of mechanical energy that is produced by the vibration of an object. In the case of musical instruments, the vibrations of strings, air columns, or membranes create sound waves that travel through the air and are detected by our ears. Traffic on the road also generates sound energy through the movement of vehicles and the vibrations they produce.
Explanation:
1. Sound energy:
- Sound energy is a form of mechanical energy that is produced by the vibration of an object.
- It is transmitted through a medium, such as air or water, in the form of sound waves.
- Sound waves are created when an object vibrates, causing particles in the medium to compress and expand, creating a series of compressions and rarefactions.
2. Musical instruments:
- Musical instruments, such as guitars, pianos, and drums, generate sound energy through the vibration of strings, air columns, or membranes.
- When a string is plucked, it vibrates, creating sound waves that travel through the air and are detected by our ears.
- Similarly, when air is blown into a flute or a trumpet, the air column inside the instrument vibrates, producing sound waves.
3. Traffic on road:
- Traffic on the road also generates sound energy due to the movement of vehicles.
- The engines, tires, and various components of vehicles produce vibrations as they operate.
- These vibrations are transmitted to the surrounding air, creating sound waves that we perceive as the noise of traffic.
Conclusion:
Musical instruments and traffic on the road are examples of sound energy because they involve the vibration of objects that generate sound waves.

The Kinetic Energy of a River
The kinetic energy of a river refers to the energy possessed by the river as a result of the movement of water. It is the energy associated with the river's flow and can be calculated using the following formula:
Kinetic energy (KE) = 0.5 * mass * velocity^2
Explanation:
1. Mechanical energy: Mechanical energy refers to the total energy of an object or system due to its motion or position. While a river does possess mechanical energy, specifically kinetic energy, it is not the correct answer in this context.
2. Chemical energy: Chemical energy is the energy stored in the bonds of chemical compounds. While chemical reactions can occur in rivers, such as the breakdown of organic matter, it is not the primary form of energy associated with the movement of water in a river.
3. Electrical energy: Electrical energy is the energy associated with the movement of electric charges. While there may be some electrical energy present in a river, such as from lightning or human-made electrical systems, it is not the primary form of energy associated with the movement of water in a river.
4. Kinetic energy: Kinetic energy is the energy possessed by an object or system due to its motion. In the context of a river, the movement of water generates kinetic energy. The faster the water flows or the greater its mass, the greater the kinetic energy of the river.
Therefore, the correct answer is Kinetic energy (D).

Question: Based on mechanical energy, which of the following is an example?
Answer:
The example based on mechanical energy is:
1. Washing machine: A washing machine uses mechanical energy to agitate and spin the clothes, which helps in cleaning and drying them.
Other options mentioned in the question are not based on mechanical energy:
2. Electronic press: An electronic press uses electrical energy to heat the plates for ironing clothes.
3. Tube light: A tube light uses electrical energy to produce light through the excitation of gas molecules.
4. LPG: LPG (liquefied petroleum gas) is a fuel source that is used for cooking and heating purposes. It is not directly related to mechanical energy.
Therefore, the correct answer is option D, washing machine, as it operates using mechanical energy.

Type of Reproduction: Asexual Reproduction
Explanation: Asexual reproduction is a type of reproduction in which an organism produces offspring that are genetically identical to itself. Here's a detailed explanation of asexual reproduction:
- Asexual Reproduction: Asexual reproduction involves the production of offspring without the involvement of gametes (sex cells) or the fusion of genetic material from two parents. It is commonly observed in many organisms, including bacteria, fungi, plants, and some animals.
- Types of Asexual Reproduction: There are various mechanisms of asexual reproduction, including:
1. Binary Fission: In this process, a parent organism divides into two equal-sized daughter cells. It is commonly seen in single-celled organisms like bacteria and protists.

2. Budding: Budding occurs when a small outgrowth (bud) develops on the parent organism and eventually detaches to become a new individual. This method is observed in organisms like yeast and Hydra.

3. Fragmentation: Fragmentation involves the breaking of the parent organism into multiple fragments, with each fragment capable of growing into a new individual. This form of reproduction is seen in organisms like flatworms and starfish.

4. Vegetative Propagation: Vegetative propagation occurs in plants, where new individuals are produced from vegetative parts such as stems, leaves, or roots. Examples include runners in strawberries and tubers in potatoes.

- Advantages of Asexual Reproduction: Asexual reproduction offers several advantages to organisms, including:
- Rapid reproduction and population growth.
- Efficient utilization of resources.
- Ability to colonize new habitats quickly.
- Preservation of favorable genetic traits in a stable environment.

- Disadvantages of Asexual Reproduction: However, asexual reproduction also has some limitations, such as:
- Lack of genetic diversity, which can make a population more susceptible to diseases and environmental changes.
- Inability to adapt to changing conditions through genetic recombination.
- Accumulation of harmful mutations over generations.

Conclusion: Asexual reproduction is a mechanism that allows organisms to produce genetically identical offspring. While it offers advantages such as rapid population growth, it also has limitations in terms of genetic diversity and adaptability.

Seedless plants reproduce by forming:
There are various methods by which seedless plants reproduce, but one of the common ways is through the formation of spores. Spores are reproductive structures that can develop into new individuals without the need for fertilization. Here is a detailed explanation of how seedless plants reproduce through spore formation:
1. Spore production: Seedless plants, such as ferns, mosses, and algae, produce spores as part of their reproductive cycle. These spores are usually single-celled structures that are capable of developing into new individuals.
2. Spore dispersal: Once the spores are mature, they are released from the parent plant and dispersed into the environment. This can happen through various mechanisms such as wind, water, or even through the movement of animals.
3. Spore germination: When a spore lands in a suitable environment, it germinates and begins to grow into a new individual. The spore contains all the necessary genetic information to develop into a mature plant.
4. Gametophyte formation: The germinating spore develops into a small, multicellular structure called a gametophyte. The gametophyte produces gametes, which are reproductive cells.
5. Fertilization: The gametes are released by the gametophyte and can fuse together to form a zygote. This process is called fertilization and results in the formation of a new sporophyte individual.
6. Sporophyte development: The zygote develops into a mature sporophyte, which is the dominant phase of the plant's life cycle. The sporophyte produces spores through meiosis, completing the reproductive cycle.
7. Continued reproduction: The mature sporophyte continues to produce spores, which are then released to start the cycle again.
In conclusion, seedless plants reproduce by forming spores, which develop into new individuals without the need for fertilization. This reproductive strategy allows seedless plants to colonize a wide range of environments and contribute to the diversity of plant life on Earth.

Pollination: The Transfer of Pollen Grains to the Female Part of the Plant
- Definition: Pollination is a process in which pollen grains are transferred from the male reproductive organ (anther) to the female reproductive organ (stigma) of a flower, enabling fertilization and reproduction in plants.
- Importance: Pollination plays a crucial role in the sexual reproduction of flowering plants, allowing for the transfer of genetic material necessary for the production of seeds and the continuation of plant species.
- Methods of Pollination: There are two main methods of pollination:
1. Self-pollination: Occurs when pollen from the anther of a flower is transferred to the stigma of the same flower or another flower on the same plant. This method ensures greater reproductive success within a single plant.
2. Cross-pollination: Occurs when pollen from the anther of one flower is transferred to the stigma of a different flower, usually from another plant of the same species. This method promotes genetic diversity and increases the chances of successful reproduction.
- Agents of Pollination: Pollination can be achieved by various agents, including:
1. Wind: Some plants have lightweight, dusty pollen that is easily carried by the wind to reach other flowers.
2. Insects: Bees, butterflies, moths, and other insects are attracted to flowers by their colors, nectar, and fragrance. As they move from flower to flower, they inadvertently transfer pollen grains.
3. Birds and Bats: Certain flowers are adapted to attract birds and bats, which carry out pollination by feeding on nectar and inadvertently transferring pollen.
4. Water: Aquatic plants rely on water currents to transport their pollen to the female reproductive organs.
- Process of Pollination: The process of pollination involves several steps:
1. Pollen Production: The male reproductive organ (anther) produces pollen grains, which contain the plant's male gametes.
2. Pollen Release: The anther releases the pollen grains, which are often contained within structures called anthers or pollen sacs.
3. Pollen Transfer: Pollen grains are transferred from the anther to the stigma, either by wind, insects, birds, bats, or water.
4. Pollen Germination: Once the pollen grains reach the stigma, they germinate, forming pollen tubes that grow down through the stigma and style, eventually reaching the ovary.
5. Fertilization: The pollen tube delivers the male gametes to the ovary, where fertilization occurs, combining the male and female gametes to form a seed.
In conclusion, pollination is the process by which pollen grains are transferred to the female part of a plant, enabling fertilization and the production of seeds. It plays a critical role in plant reproduction and is accomplished through various agents and methods.

The four main parts of a flower are the petals, sepals, stamen, and carpel (sometimes known as a pistil). If a flower has all four of these key parts, it is considered to be a complete flower.

So stem is not a main part