General Science MCQ Quiz - Objective Question with Answer for General Science - Download Free PDF

The correct answer is Watt.

Key Points

• Watt (W) is the SI unit of power, named after James Watt, a Scottish inventor and mechanical engineer.
• One watt is defined as the rate of energy transfer equivalent to one joule per second (1 W = 1 J/s).
• The unit is commonly used to quantify the rate at which electrical energy is consumed or produced in electrical circuits.
• Power is a scalar quantity, meaning it has magnitude but no direction.

Additional Information

• Joule (J)
  • It is the SI unit of energy, named after James Prescott Joule.
  • One joule is the energy transferred when one newton of force moves an object one meter.
  • It is also used to express electrical energy, where one joule is equal to one watt-second.
• Ampere (A)
  • It is the SI unit of electric current, named after André-Marie Ampère.
  • One ampere represents the flow of one coulomb of charge per second.
  • It is used to measure the amount of electric charge passing a point in an electrical circuit per unit time.
• Volt (V)
  • It is the SI unit of electric potential, named after Alessandro Volta.
  • One volt is defined as the potential difference that will drive one ampere of current against one ohm of resistance.
  • It is used to measure the electrical potential difference between two points.
• Power in Electrical Circuits
  • Power (P) in an electrical circuit is calculated using the formula P = IV, where I is current (in amperes) and V is voltage (in volts).
  • Another common formula is P = I²R, where R is resistance (in ohms).
  • Power can also be expressed as P = V²/R.

The correct answer is Cerebellum.

Key Points

• The cerebellum is located at the back of the brain, underneath the occipital lobes.
• It plays a crucial role in motor control, particularly in coordinating voluntary movements.
• The cerebellum helps maintain balance and posture by integrating sensory information from the spinal cord and other parts of the brain.
• It is involved in motor learning, allowing the body to perform smooth, accurate, and balanced movements.
• Damage to the cerebellum can result in ataxia, which is characterized by a lack of coordination and control over movements.

Additional Information

• Cerebrum
  • The cerebrum is the largest part of the human brain and is responsible for higher brain functions such as thought, action, and sensory processing.
  • It is divided into two hemispheres, each of which is further divided into lobes responsible for different functions.
  • The cerebrum controls voluntary muscle movements and is involved in cognitive functions like learning and memory.
• Medulla
  • The medulla oblongata is located in the brainstem and controls autonomic functions like breathing, heart rate, and blood pressure.
  • It acts as a relay station, transmitting signals between the brain and the spinal cord.
• Hypothalamus
  • The hypothalamus is a small region located below the thalamus and is crucial for maintaining homeostasis in the body.
  • It regulates various autonomic functions such as temperature control, hunger, thirst, and circadian rhythms.
  • The hypothalamus also plays a role in hormone secretion through its interaction with the pituitary gland.

The correct answer is Option 2.

Key Points

• Water is a universal solvent: Water can dissolve more substances than any other liquid, which makes it essential for biological processes and various industrial applications.
• Water has a high boiling point: Water boils at 100°C (212°F) under standard atmospheric pressure, which is relatively high compared to other similar molecular compounds.
• Water is a poor conductor of electricity: Pure water does not conduct electricity well. Its conductivity increases with the addition of dissolved salts and minerals.
• Water exists in all three states on Earth: Water naturally occurs as a solid (ice), liquid (water), and gas (water vapor) in the Earth's environment.

Additional Information

• Universal Solvent:
  • Water's polarity allows it to dissolve a wide range of substances, making it crucial for chemical reactions in living organisms and industrial processes.
  • This property is essential for nutrient transport in biological systems and for the functioning of ecosystems.
• High Boiling Point:
  • Water's high boiling point is due to hydrogen bonding among water molecules, which requires significant energy to break.
  • This high boiling point helps regulate temperature in natural and artificial environments.
• Electrical Conductivity:
  • Pure water's low electrical conductivity is due to the lack of free ions; however, the presence of dissolved ions like sodium and chloride increases its conductivity.
  • Understanding water's conductivity is important for water quality assessment and various industrial applications.
• States of Water:
  • Water's ability to exist in three states is due to its unique molecular structure and hydrogen bonding.
  • This property is vital for Earth's climate system, influencing weather patterns and the hydrological cycle.

The correct answer is Combustion of fuel.

Key Points

• The combustion of fuel is a chemical reaction between fuel and an oxidant, releasing energy in the form of heat and light.
• This process is exothermic because it releases more energy than it absorbs.
• Common examples of fuels include hydrocarbons such as gasoline, diesel, and natural gas.
• The energy released during combustion is utilized in various applications such as power generation, heating, and propulsion.
• Combustion reactions are crucial in industries and everyday life, driving engines and generating electricity.

Additional Information

• Exothermic Reactions
  • Exothermic reactions are chemical reactions that release energy in the form of heat.
  • These reactions typically involve the breaking of bonds in reactants and the formation of new bonds in products, with a net release of energy.
  • Examples include combustion, respiration, and many oxidation-reduction reactions.
  • The released energy often increases the temperature of the surroundings.
• Endothermic Reactions
  • Endothermic reactions are chemical reactions that absorb energy from their surroundings.
  • These reactions require an input of energy to proceed, typically in the form of heat.
  • Examples include photosynthesis, melting of ice, and evaporation of water.
  • Endothermic reactions result in a decrease in the temperature of the surroundings.
• Combustion Process
  • Combustion involves a rapid chemical reaction between a fuel and an oxidant, producing heat and light.
  • It usually produces carbon dioxide (CO2) and water (H2O) as byproducts.
  • Incomplete combustion can produce carbon monoxide (CO) and other harmful substances.
  • Proper ventilation and control of fuel-to-oxidant ratio are crucial to ensure complete combustion.
• Applications of Combustion
  • Combustion is widely used in power plants to generate electricity.
  • It is the driving force behind internal combustion engines in vehicles.
  • Combustion is essential in heating systems such as furnaces and boilers.
  • It plays a key role in various industrial processes, including metal smelting and waste incineration.

The correct answer is Option 2.

Key Points

• Water: Water has the highest specific heat capacity among common substances, which means it can absorb a lot of heat without a significant increase in temperature.
• Mercury: Mercury is a good conductor of electricity and is used in thermometers and electrical switches.
• Iron: Iron is solid at room temperature and is widely used in construction and manufacturing due to its strength and durability.
• Helium: Helium is the least dense gas, making it useful for applications like filling balloons and as a coolant in scientific equipment.

Additional Information

• Specific Heat Capacity: It is the amount of heat required to raise the temperature of one gram of a substance by one degree Celsius.
• Conductivity: Conductivity is the ability of a material to conduct electricity or heat. Metals like mercury and copper are good conductors.
• Density: Density is the mass per unit volume of a substance. Helium, being the least dense gas, is lighter than air.
• Room Temperature: Room temperature is typically considered to be around 20-25 degrees Celsius (68-77 degrees Fahrenheit).
• Applications of Helium: Helium is used in various applications such as cryogenics, deep-sea breathing systems, and as a protective gas in welding.

The correct answer is Protein synthesis.

Key Points

• Ribosomes are membranous granular structures present in the cytoplasm.
• They were first observed under an electron microscope as dense particles by George Palade in the year 1953.
• Ribosomes are the site for ''protein synthesis'' so they are also called the ''protein factory'' of the cell.
• There are two types of ribosomes

1. Eukaryotic ribosomes - 80s - occurs in the cytoplasm of eukaryotic cell
2. Prokaryotic ribosomes - 70s - occur in the cytoplasm as well as are associated with the cell membrane of prokaryotic cell.

• The subunits of the ribosomes are:
  • 80s ribosomes - are made of 60s and 40s subunits.
  • 70s ribosomes - are made of 50s and 30s subunits.

Important Points

• Composition of the structure of ribosome:
• They are composed of ribonucleic acid (RNA) and proteins

Additional Information

• Photosynthesis: It is the process by which green plants and some other organisms use sunlight to synthesize nutrients from carbon dioxide and water. In this process, plant the chlorophyll, carbon dioxide, water, sunlight, and release oxygen.
• Synthesis of Fatty acids occurs in the cytoplasm.

CONCEPT:

• Wave: The disturbance that transfers energy from one place to another is called a wave.

There are mainly two types of waves:

1. Transverse waves: The wave in which the movement of the particles is at right angles to the motion of the energy is called a transverse wave. Light is an example of a transverse wave.
2. Longitudinal wave: The wave in which the movement of the particles is parallel to the motion of the energy is called a longitudinal wave. The sound wave is an example of a longitudinal wave.

EXPLANATION:

• Light-wave is a transverse wave because its components vibrate perpendicular to its direction of propagation. So option 1 is correct.

The correct answer is Newton's first law.

Key Points

• Newton's laws of motion-
  • ​Newton’s first law states that, if a body is at rest or moving at a constant speed in a straight line, it will remain at rest or keep moving in a straight line at constant speed unless it is acted upon by force.
    • This postulate is known as the law of inertia. The law of inertia was first formulated by Galileo Galilei for horizontal motion on Earth and was later generalized by René Descartes.
    • Before Galileo, it had been thought that all horizontal motion required a direct cause. Still, Galileo deduced from his experiments that a body in motion would remain in motion unless a force (such as friction) caused it to come to rest.
  • Newton’s second law is a quantitative description of the changes that a force can produce in a body's motion.
    • It states that the time rate of change of a body's momentum is equal in both magnitude and direction to the force imposed on it.
    • The momentum of a body is equal to the product of its mass and its velocity. Momentum, like velocity, is a vector quantity, having both magnitude and direction.
    • A force applied to a body can change the magnitude of the momentum, direction, or both.
    • For a body whose mass m is constant, it can be written in F = ma, where F (force) and an (acceleration) are vector quantities.
    • If a body has a net force acting on it, it is accelerated by the equation. Conversely, if a body is not accelerated, there is no net force acting on it.
  • Newton’s third law states that when two bodies interact, they apply forces to one another that are equal in magnitude and opposite in direction.
  • The third law is also known as the law of action and reaction. This law is important in analyzing static equilibrium problems, where all forces are balanced, but it also applies to bodies in uniform or accelerated motion.
  • The forces it describes are real ones, not mere bookkeeping devices. For example, a book resting on a table applies a downward force equal to its weight on the table.
  • According to the third law, the table applies an equal and opposite force to the book. This force occurs because the book's weight causes the table to deform slightly so that it pushes back on the book like a coiled spring.

The correct answer is Bile juice, Pancreatic juice.

Key Points

• Bile juice, Pancreatic juice secreted by the organs plays an important role in the digestion of fats.
• Bile juice is secreted by the liver.
  • It does not contain any types of enzymes.
  • The bile juice helps to make the food alkaline and break down the fat molecules.
• Pancreatic juice is secreted by the pancreas.
  • It contains enzymes like amylase, trypsin, pancreatic lipase, nucleases and lipase.
  • Secretion of the Pancreatic juice is regulated by the hormones secretin and cholecystokinin.
• Lipase is the digestive enzyme of fat.
• Ptyalin is the digestive enzyme of the Saliva.
• Hydrochloric acid is produced naturally in the human stomach to help the digestion of food.

Concept:

Photosynthesis: 

• The leaves have a green pigment called chlorophyll.
• It helps leaves to capture the energy of the sunlight.
• This energy is used to synthesise (prepare) food from carbon dioxide and water. Since the synthesis of food occurs in the presence of sunlight, it is called photosynthesis.

In the presence of sunlight Carbon dioxide + water → Carbohydrate + oxygen.

• Some plants, green algae, and cyanobacteria can perform photosynthesis.
• The process of photosynthesis is commonly written as

                   6CO2 + 6H2O + Sun-Light → C6H12O6 + 6O2

Plant cells have a cell wall to protect them and make them rigid structure.

Explanation:

1. Plants convert energy from sunlight into food stored as carbohydrate’s - Correct

2. Plants have chlorophyll. - Correct

3. Plant cells do not have cell walls. - Incorrect.

Additional Information

In the plant cells, there are different components and organelles for specific functions-

• Cell Wall – It is a rigid layer composed of cellulose. It is the outermost layer of the cell, below this cell membrane is present. The primary function of the cell wall is to protect and provide structural support to the cell.
• Cell Membrane – It is a semi-permeable membrane that helps in regulating and the substance for entry and exit inside and outside the cell.
• Nucleus – It is a vital part of the cell as it contains all the information or DNA of the cell and their heredity information for growth and cell division.
• Vacuole – Most of the part of the plant cell is occupied by the vacuole. It is surrounded by Tonoplast. The vital role of the vacuole is to provide support again the pressure of the cell wall.
• Golgi apparatus – They act as a transport system in the cell, as they transport various molecules to a different part of the cell.
• Ribosomes – They are the sites of protein synthesis, also termed as the protein factory of the cell.
• Mitochondrion – They break the complex molecules and produce energy and hence called the powerhouse of the cell.
• Lysosomes – They are termed suicidal bags as they hold the enzymes that are capable to digest the whole cell itself.

The correct answer is Whale.

Key Points

• Gills are respiratory organs found in most aquatic organisms.
• Gills can extract dissolved oxygen from water and excrete carbon dioxide.
• Gills can be found in Octopus, Squid, Clownfish, Tadpole, Prawn, etc.
• Lungs are the breathing organ of Whales.

Additional InformationRespiratory organs of different Animals:

The correct answer is Both chloroplast and mitochondria

Concept:

Theory of endosymbiosis:-

• Symbiotic relationship, where one organism lives inside the other, is known as endosymbiosis. 
• The theory proposed that mitochondria and chloroplasts evolved from engulfed prokaryotes.
• A large anaerobic bacteria engulfed an aerobic prokaryote, which then formed an endosymbiotic relationship with the host, gradually developing into a mitochondrion.
• It is believed that chloroplasts originated from a cyanobacterial endosymbiont.

Explanation:

Similarities between Prokaryotic cells, Mitochondria, and Chloroplast:

• Mitochondria and chloroplast are of the same size as prokaryotic cells.
• Mitochondria and prokaryotic cells both have their own circular DNA.
• The ribosome of bacteria, mitochondria, and chloroplasts have a 70S type of ribosome.
• Divides by binary fission.

• Vitamin K is a vitamin found in leafy green vegetables, broccoli, and Brussels sprouts.
• In the body, vitamin K plays a major role in blood clotting. So it is used to reverse the effects of “blood-thinning” medications when too much is given; to prevent clotting problems in newborns who don’t have enough vitamin K, and to treat bleeding caused by medications.

Tricks:

The correct answer is At the centre of the Earth.

• The centre of the Earth is such that if we are at that place, the mass around us can be considered to be condensed at the surface of the Earth itself, i.e considering the Earth as a spherical shell.
• Inside a spherical shell, there is no change in potential as one moves inside, and since only a change in potential implies a force there is no force.
• Hence the acceleration due to gravity is zero at the centre of the Earth.