Question 1

Which vitamin is known as the 'Anti-Sterility' vitamin?

Accepted Answer

Correct Answer: Vitamin E

Explanation: Vitamin E is often referred to as the Anti-Sterility vitamin because its deficiency can lead to reproductive failure and infertility in animals. It acts as a powerful antioxidant, protecting cells from oxidative stress. It is found in vegetable oils, nuts, seeds, and green leafy vegetables.

Question 2

The speed of sound is maximum in:

Accepted Answer

Correct Answer: Steel (Solid)

Explanation: Sound travels fastest in solids like steel (approx 5000 m/s) because the molecules are tightly packed, allowing the vibration wave to transfer energy rapidly. It travels slower in liquids (water approx 1480 m/s) and slowest in gases (air approx 343 m/s). Sound cannot travel at all in a vacuum.

Question 3

The hardest substance in the human body is:

Accepted Answer

Correct Answer: Enamel

Explanation: Tooth Enamel is the hardest and most highly mineralized substance in the human body. It contains a high percentage of hydroxyapatite crystals, making it incredibly durable to withstand the forces of chewing and biting. However, unlike bone, enamel cannot regenerate if it is chipped or eroded by acid.

Question 4

Which instrument is used to detect the lie?

Accepted Answer

Correct Answer: Polygraph

Explanation: A Polygraph, commonly known as a lie detector, is used to detect physiological changes that occur when a person lies. It measures indicators such as blood pressure, pulse, respiration, and skin conductivity (sweating) while the subject answers a series of questions. The assumption is that deceptive answers produce physiological responses different from non-deceptive ones.

Question 5

The weight of a body at the center of the Earth is:

Accepted Answer

Correct Answer: Zero

Explanation: At the center of the Earth, the weight of a body becomes zero. This is because the gravitational pull is exerted equally from all directions by the Earth's mass surrounding the object. These forces cancel each other out, resulting in a net gravitational force of zero. However, the mass of the object remains unchanged.

Question 6

Which is the closest Galaxy to our Milky Way?

Accepted Answer

Correct Answer: Andromeda

Explanation: The Andromeda Galaxy is the nearest major galaxy to the Milky Way, located about 2.5 million light-years away. It is a spiral galaxy like ours but larger. Astronomers predict that Andromeda and the Milky Way will collide and merge in about 4.5 billion years to form a giant elliptical galaxy.

Question 7

The wire of an electric fuse is made of:

Accepted Answer

Correct Answer: Lead-Tin Alloy

Explanation: An electric fuse wire is made of an alloy of Lead and Tin (solder). This alloy has a low melting point and high resistance. If the current in the circuit exceeds a safe limit, the wire heats up and melts (blows), breaking the circuit and preventing damage to expensive appliances or fire hazards.

Question 8

Which gas is mainly responsible for the Ozone Hole?

Accepted Answer

Correct Answer: CFCs (Chlorofluorocarbons)

Explanation: Chlorofluorocarbons (CFCs) are the primary cause of ozone layer depletion. These chemicals were widely used in refrigerators, air conditioners, and aerosol sprays. When released, they float up to the stratosphere where UV radiation breaks them down, releasing chlorine atoms. A single chlorine atom can destroy thousands of ozone molecules.

Question 9

The Study of Fossils is called:

Accepted Answer

Correct Answer: Paleontology

Explanation: Paleontology is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene Epoch. It involves the analysis of plant and animal fossils, including microscopic ones, to determine their evolution and interaction with each other and their environments. It helps us understand the history of life on Earth, including dinosaurs.

Question 10

Which is the longest cell in the human body?

Accepted Answer

Correct Answer: Nerve Cell (Neuron)

Explanation: The Nerve Cell, or Neuron, is the longest cell in the human body. Some neurons, like the sciatic nerve, can extend from the base of the spine all the way down to the big toe, measuring over a meter in length. Their long structure (axon) allows them to transmit electrical signals rapidly across long distances in the body.

Question 11

What creates the 'Mirage' effect in deserts?

Accepted Answer

Correct Answer: Total Internal Reflection

Explanation: A Mirage is an optical illusion caused by Total Internal Reflection and refraction. In a hot desert, the air near the ground is much hotter (and less dense) than the air above. Light rays from the sky bend as they pass through these layers, eventually reflecting upwards to the observer's eye. This makes the ground look like a pool of water reflecting the sky.

Question 12

Which gas is filled in cigarette lighters?

Accepted Answer

Correct Answer: Butane

Explanation: Cigarette lighters are filled with Butane gas. Butane is easily liquefied under pressure, allowing a large amount of fuel to be stored in a small plastic container. When the valve is opened, the liquid turns back into gas, which ignites with a spark. It burns cleanly and produces a consistent flame.

Question 13

Who invented Dynamite?

Accepted Answer

Correct Answer: Alfred Nobel

Explanation: Alfred Nobel, a Swedish chemist, invented Dynamite in 1867. Before this, explosives like nitroglycerin were extremely unstable and dangerous to transport. Nobel stabilized nitroglycerin using a substance called diatomaceous earth. The wealth he earned from his explosives business was later used to establish the Nobel Prizes.

Question 14

Where are Red Blood Cells (RBCs) produced?

Accepted Answer

Correct Answer: Bone Marrow

Explanation: Red Blood Cells are produced in the Red Bone Marrow, a spongy tissue found inside the hollow centers of large bones like the femur and hip bone. The process is called erythropoiesis. The marrow releases millions of RBCs into the bloodstream every second to replace old ones that are destroyed.

Question 15

What is the unit of Power?

Accepted Answer

Correct Answer: Watt

Explanation: The SI unit of Power is the Watt (W). It is named after James Watt, the inventor of the steam engine. One Watt is defined as one Joule of energy transferred or work done per second. It is commonly used to rate light bulbs, engines, and electrical appliances. 1000 Watts equal 1 Kilowatt.

Question 16

Density of water is maximum at:

Accepted Answer

Correct Answer: 4°C

Explanation: Water has a unique property where its density is maximum at 4°C. As water cools from 4°C down to 0°C, it expands and becomes less dense (which is why ice floats). This anomaly is crucial for marine life; in winter, only the top layer of a lake freezes, while the water at the bottom remains liquid at 4°C, allowing fish to survive.

Question 17

Which organism is known as the 'Farmer's Friend'?

Accepted Answer

Correct Answer: Earthworm

Explanation: The Earthworm is called the Farmer's Friend because it improves soil health. As earthworms burrow through the soil, they aerate it, allowing air and water to reach plant roots. They also consume organic matter and excrete nutrient-rich waste (castings) that acts as a natural fertilizer, significantly boosting crop yield.

Question 18

The chemical name of Washing Soda is:

Accepted Answer

Correct Answer: Sodium Carbonate

Explanation: Washing Soda is chemically known as Sodium Carbonate (Na2CO3). It is different from baking soda. It is a strong alkaline substance used in cleaning laundry, removing grease, and softening water. It absorbs moisture from the air and is used in the manufacture of glass, paper, and soap.

Question 19

Which color of light has the longest wavelength?

Accepted Answer

Correct Answer: Red

Explanation: In the visible light spectrum, Red light has the longest wavelength and the lowest frequency. Violet has the shortest wavelength and highest frequency. This is why red light is used in traffic signals and brake lights—it scatters the least in the atmosphere and can be seen from a long distance, even through fog or rain.

Question 20

Who is considered the 'Father of Biology'?

Accepted Answer

Correct Answer: Aristotle

Explanation: Aristotle, the ancient Greek philosopher, is widely considered the Father of Biology. He was the first to systematically study and classify living organisms. He observed animals, dissected them, and categorized them based on their features (e.g., with blood vs. without blood). His work laid the foundation for the biological sciences for centuries.

Everyday Science MCQs