Everyday Science MCQs in topical order.

Correct Answer: None of these

While some bacteria can act as parasites, they as a whole group are highly diverse single-celled organisms that do not uniformly fit into 'parasites' or 'predators'.

Correct Answer: Throat

The tonsils are clusters of lymphatic tissue situated at the back of the human throat.

Correct Answer: Carbon dioxide

At night, photosynthesis stops, and plants release carbon dioxide, which can make the air quality under a dense tree canopy less favorable.

Correct Answer: Caffeine

Caffeine is the primary stimulant alkaloid found in tea leaves (often historically referred to as 'theine' in tea).

Correct Answer: Virus

Influenza, or the flu, is an infectious disease caused by an influenza virus.

Correct Answer: Fats

Fats provide the highest calorific value, yielding approximately 9 kilocalories per gram, compared to 4 kcal/g for proteins and carbohydrates.

Correct Answer: Golgi apparatus

While lysosomes physically store the degradative enzymes, the Golgi apparatus modifies, sorts, and packages these enzymatic proteins into vesicles.

Correct Answer: 23 pairs

A normal human cell contains 46 chromosomes, arranged into 23 pairs.

Correct Answer: Radon

Radon is a naturally occurring radioactive gas that can accumulate in poorly ventilated buildings and is a health hazard.

Correct Answer: Deliquescence

Deliquescence is the process by which a substance absorbs moisture from the atmosphere until it dissolves completely in the absorbed water.

Correct Answer: Hydrogen

Hydrogen is a highly combustible diatomic gas, whereas oxygen supports combustion but is not itself flammable in the same way.

Correct Answer: Copper

Cu stands for Cuprum, which is the Latin name for Copper.

Correct Answer: 6.7

The typical pH of fresh cow's milk is slightly acidic, ranging from 6.5 to 6.7.

Correct Answer: Lowering of interfacial tension

Soaps and detergents work by lowering the surface tension of water, allowing it to wet fabrics better and trap dirt.

Correct Answer: None of these

Bronze is primarily an alloy of copper and tin. (Copper and zinc make brass).

Correct Answer: Goldstein

Eugen Goldstein discovered positive particles (canal rays) in 1886, laying the foundation for the proton, which was later named and confirmed by Rutherford.

Correct Answer: Radio waves

Mobile phones communicate wirelessly by transmitting and receiving radio frequency (RF) signals, which are a type of electromagnetic wave.

Correct Answer: Diffusion

Diffusion is the net movement of particles from a region of higher concentration to one of lower concentration.

Correct Answer: 9%

When water transforms into ice, it expands by approximately 9% due to the formation of a crystalline structure.

Correct Answer: Steel

Elasticity is defined by a material's ability to return to its original shape; steel is more elastic than rubber according to Young's Modulus.

Correct Answer: Density

Ice is less dense than liquid water, which allows it to float.

Correct Answer: Glass or plastic

Optical fibers are flexible, transparent fibers made by drawing glass (silica) or plastic to a diameter slightly thicker than that of a human hair.

Correct Answer: Sound cannot travel through a vacuum

Sound is a mechanical wave that requires a material medium (like gas, liquid, or solid) to propagate, and thus it cannot travel through a vacuum.

Correct Answer: Mechanical Energy

Mechanical energy is the sum of an object's kinetic and potential energy.

Correct Answer: Mercury

Mercury is the smallest planet in the Solar System and the closest to the Sun.

Correct Answer: 6,000 K

The photosphere, or the visible surface of the Sun, has a temperature of approximately 5,800 to 6,000 Kelvin.

Correct Answer: 380,000 km

The average orbital distance from the Earth to the Moon is approximately 384,400 km.

Correct Answer: 8 minutes 20 seconds

Light travels at roughly 300,000 km/s and the sun is 150 million km away, taking approximately 500 seconds (8 min 20 sec) to reach Earth.

Correct Answer: Venus

Venus is highly reflective and is visible shortly before sunrise or after sunset, earning it the nickname Morning Star or Evening Star.

Correct Answer: Astronomy

Astronomy is the natural science that studies celestial objects and phenomena, including stars, planets, and galaxies.

Correct Answer: Full Moon

A lunar eclipse occurs only during a full moon, when the Earth moves precisely between the Sun and the Moon.

Correct Answer: Neptune

According to Kepler's laws of planetary motion, the further a planet is from the sun, the slower its orbital speed. Neptune is the furthest and slowest.

Correct Answer: 17-30

Wisdom teeth, or third molars, typically emerge in the back of the mouth between the late teens and late twenties.

Correct Answer: 120

Human red blood cells (erythrocytes) have an average lifespan of about 100 to 120 days before they are removed by the spleen and liver.

Correct Answer: 70-80 times

A normal resting heart rate for adults ranges from 60 to 100 beats per minute, commonly averaging between 70 and 80 beats.

Correct Answer: 206

The skeletal system of an adult human consists of exactly 206 bones, down from around 270 at birth due to fusion.

Correct Answer: Cerebrum

The cerebrum is the largest part of the brain, responsible for higher functions like thought, action, and emotion.

Correct Answer: 206

A typical adult human skeleton consists of exactly 206 bones, varying slightly in rare anatomical cases.

Correct Answer: Eyesight

Myopia, or nearsightedness, is a common vision condition affecting the eyes where close objects appear clearly, but far ones don't.

Correct Answer: None of these

Blood group O-negative is known as the universal donor type because it lacks A, B, and Rh antigens.

Correct Answer: 1973

Martin Cooper, an engineer at Motorola, made the first public mobile telephone call on a handheld device on April 3, 1973.

Correct Answer: Graham

Alexander Graham Bell is widely credited with inventing and patenting the first practical telephone in 1876.

Correct Answer: Rene Laennec

The stethoscope was invented in 1816 by the French physician René Laennec.

Correct Answer: Bulb

Thomas Edison is most famously credited with inventing the first commercially practical incandescent light bulb.

Correct Answer: Wright Brothers

Orville and Wilbur Wright built and flew the first successful, fully practical airplane in 1903.

Correct Answer: Montgolfier Brothers

The Montgolfier brothers, Joseph-Michel and Jacques-Étienne, successfully demonstrated the first public flight of a hot air balloon in 1783.

Correct Answer: Benjamin Franklin

Benjamin Franklin is credited with inventing the lightning rod in 1752 to protect buildings from lightning strikes.

Correct Answer: Benjamin Franklin

Benjamin Franklin invented the lightning rod in 1752 as a way to protect buildings from lightning strikes.

Correct Answer: China

China is currently the world's largest emitter of carbon dioxide and greenhouse gases, largely due to its massive industrial sector and reliance on coal.

Correct Answer: Atmosphere

Incoming solar radiation is partially absorbed, scattered, and reflected back into space by various layers, clouds, and gases in the Earth's atmosphere.

Correct Answer: None of these

Conservation reports indicate that illegal poaching has caused the pangolin population in Pakistan to decline by over 80%.

Correct Answer: Carbon Dioxide (CO2)

Carbon dioxide is a primary greenhouse gas that traps heat in the Earth's atmosphere, contributing significantly to global warming.

Correct Answer: Global warming

Greenhouse gases trap heat in the Earth's atmosphere, leading to a steady rise in global temperatures, known as global warming.

Correct Answer: Global Change Impact

Climate change and global warming impacts cause extreme weather events like prolonged droughts and severe temperature changes.

Correct Answer: All of these

Water sagacity, or water stewardship, is essential across all sectors, including industrial, agricultural, and domestic usage, to ensure sustainability and conservation.

Correct Answer: Soil erosion

Deforestation removes the root systems that hold soil together, leading to an increase in soil erosion.

Correct Answer: Hydrochloric acid

The stomach produces hydrochloric acid (HCl), which breaks down food and activates digestive enzymes like pepsin.

Correct Answer: 120/80 mmHg

A normal human blood pressure reading is typically around 120 over 80 millimeters of mercury (systolic/diastolic).

Correct Answer: 5-21 days

The lifespan of most white blood cells falls roughly within the range of 5 to 21 days, though some memory cells live for years.

Correct Answer: Antigen

Blood types (A, B, AB, and O) are classified based on the presence or absence of inherited antigenic substances on the surface of red blood cells.

Correct Answer: To express our feelings

Laughter is a physical reaction in humans consisting of rhythmic, often audible contractions of the diaphragm and other parts of the respiratory system to express joy or amusement.

Correct Answer: Bone Marrow

The primary site of red blood cell production (erythropoiesis) in adults is the red bone marrow.

Correct Answer: 1.5 kg

The average adult human brain weighs roughly between 1.3 to 1.5 kilograms.

Correct Answer: Protein

Blood clotting involves coagulation factors, which are primarily proteins like fibrinogen that transform into a fibrin mesh.

Correct Answer: Blood

Leukemia is a form of cancer that affects the blood and bone marrow, characterized by abnormal white blood cell production.

Correct Answer: Virus

COVID-19 is an infectious disease caused by the SARS-CoV-2 virus.

Correct Answer: Virus

Polio, or poliomyelitis, is an infectious disease caused by the poliovirus.

Correct Answer: Aedes Aegypti

Dengue fever is transmitted by the bite of an Aedes mosquito infected with a dengue virus, most commonly Aedes aegypti.

Correct Answer: Smallpox

Smallpox is the only infectious human disease to have been completely eradicated globally, certified by the WHO in 1980.

Correct Answer: Uganda

The Zika virus was first isolated in 1947 in a rhesus macaque monkey in the Zika Forest of Uganda.

Correct Answer: Leukaemia

Leukaemia is a broad term for cancers of the blood cells, usually beginning in the bone marrow and resulting in high numbers of abnormal blood cells.

Correct Answer: Spleen

The malaria parasite (Plasmodium) primarily infects red blood cells, which are filtered by the spleen, often leading to an enlarged spleen (splenomegaly).

Correct Answer: Increased amount of UV rays will reach Earth's surface

The ozone layer filters out harmful ultraviolet (UV) radiation; its depletion allows more UV light to reach Earth.

Correct Answer: All of these

Acid rain negatively impacts ecosystems by harming aquatic life, damaging forests, and accelerating the weathering of limestone and marble buildings.

Correct Answer: Carbon dioxide

Due to fossil fuel emissions, excess carbon dioxide is the primary greenhouse gas driving anthropogenic global warming.

Correct Answer: Chlorofluorocarbon

CFCs release chlorine atoms into the stratosphere under UV radiation, which act as catalysts heavily destroying ozone molecules.

Correct Answer: Nitrogen

Nitrogen makes up roughly 78% of the Earth's atmosphere and is a benign, stable gas in its diatomic form, unlike compounds of carbon or chlorine which are often pollutants.

Correct Answer: CO2

Carbon dioxide (CO2) is a primary greenhouse gas that contributes to global warming by trapping heat in the Earth's atmosphere.

Correct Answer: Sulphuric Acid & Nitric Acid

Acid rain is caused by emissions of sulfur dioxide and nitrogen oxide, which react with water molecules in the atmosphere to produce sulfuric and nitric acids.

Correct Answer: Carbon monoxide

Internal combustion engines in cars emit Carbon Monoxide (CO), an invisible, highly toxic gas.

Correct Answer: Vitamin B & Vitamin C

Both Vitamin B complex and Vitamin C are classified as water-soluble vitamins, meaning they dissolve in water and are not stored in the body.

Correct Answer: Vitamin B

Deficiencies in B-complex vitamins (especially B1, B6, B12) are directly linked to severe neurological and muscular dysfunctions.

Correct Answer: Vitamin K

Vitamin K is an essential nutrient that the body needs for blood clotting, which helps wounds heal.

Correct Answer: Vitamin D

Vitamin D is synthesized in the skin in response to exposure to ultraviolet rays from sunlight.

Correct Answer: Vitamin C

Vitamin C (ascorbic acid) is vital for the synthesis of collagen, a structural protein necessary for tissue repair and wound healing.

Correct Answer: E

Selenium works synergistically with Vitamin E as an antioxidant to protect cells from damage caused by free radicals.

Correct Answer: Vitamin K

Vitamin K is an essential nutrient required by the body to produce certain proteins crucial for the coagulation (clotting) of blood.

Correct Answer: Vitamin E

Vitamin E deficiency can cause nerve and muscle damage that results in loss of feeling in the arms and legs, loss of body movement control, and muscle weakness.

Correct Answer: White light

White light contains all wavelengths of the visible spectrum, ensuring plants can absorb maximum energy across peaks like red and blue.

Correct Answer: Plants & Fruits

Horticulture is the branch of agriculture that deals with the art and science of plant cultivation, including fruits, vegetables, and ornamental plants.

Correct Answer: Horticulture

Horticulture is the branch of agriculture that deals with the art, science, and business of growing fruits, vegetables, flowers, and ornamental plants.

Correct Answer: Wheat Grain

Botanically, a wheat grain is a type of dry, single-seeded fruit known as a caryopsis, but in common agricultural parlance and dietary contexts, it is classified as a cereal grain, making it the odd one out among typical fleshy fruits.

Correct Answer: Transpiration

Transpiration is the biological process by which moisture is carried through plants from roots to small pores on the underside of leaves, where it changes to vapor and is released to the atmosphere.

Correct Answer: Carbon dioxide

At night, in the absence of sunlight, photosynthesis stops but respiration continues, causing plants to take in oxygen and exhale carbon dioxide.

Correct Answer: Iodine

While iron, zinc, and potassium are essential micronutrients and macronutrients for plant growth, iodine is not required for plant survival.

Correct Answer: Sphenopsids

Sphenopsids (like horsetails) are often called arthrophytes due to their distinctly jointed stems.