Medium Science Trivia Questions

33 medium science trivia questions with answers

1. What is the hardest known natural substance?

   Answer: Diamond It is pure carbon, arranged in a rigid three-dimensional lattice.Why?

2. How many chambers does the human heart have?

   Answer: Four Two atria receive blood and two ventricles pump it out.Why?

3. What does DNA stand for?

   Answer: Deoxyribonucleic acid Its double-helix structure was described by Watson, Crick and Franklin's data.Why?

4. Which scientist proposed the three laws of motion?

   Answer: Isaac Newton He set them out in the Principia, published in 1687.Why?

5. What is the speed of light in a vacuum, to the nearest round figure?

   Answer: 300,000 km per second Nothing carrying information can travel faster than this limit.Why?

6. What blood type is known as the universal donor for red blood cells?

   Answer: O negative It carries neither A, B nor Rh D antigens for a recipient to react against.Why?

7. Sound cannot travel through which of these?

   Answer: A vacuum It needs particles to pass the vibration along, so space is silent.

8. Which scientist developed the theory of general relativity?

   Answer: Albert Einstein It describes gravity as the bending of space and time by mass.Why?

9. The periodic table arranges elements by which property?

   Answer: Atomic number Atomic number is simply the count of protons in the nucleus.

10. Which blood cells carry oxygen around the body?

    Answer: Red blood cells They use haemoglobin, an iron-containing protein, to bind the oxygen.Why?

11. Which gas makes up the ozone layer that filters ultraviolet light?

    Answer: Ozone Ozone is a molecule of three oxygen atoms rather than the usual two.Why?

12. An animal that eats only plants is described as what?

    Answer: Herbivore Many have specialised guts or extra stomachs to break down cellulose.

13. Which unit measures electrical resistance?

    Answer: Ohm Ohm's law ties it to voltage and current in a single relationship.Why?

14. Which layer of Earth lies directly beneath the crust?

    Answer: The mantle Slow convection in it drives the movement of tectonic plates.Why?

15. Roughly how long does sunlight take to reach Earth?

    Answer: About 8 minutes The Sun is about 150 million kilometres away and light covers 300,000 kilometres each second.

16. Which planet spins almost on its side, with its axis tilted about 98 degrees?

    Answer: Uranus Each pole gets around 42 years of continuous sunlight followed by 42 years of darkness.

17. Why does the Moon shine at night?

    Answer: It reflects sunlight The surface reflects only about 12 percent of the light that hits it, roughly like worn asphalt.

18. Which is the hottest planet in the solar system?

    Answer: Venus Its thick carbon dioxide atmosphere traps heat, making it hotter than Mercury despite being further from the Sun.

19. Rock formed from cooled magma or lava is called what?

    Answer: Igneous Granite cools slowly underground while basalt cools quickly at the surface.

20. The supercontinent that existed about 250 million years ago is known as what?

    Answer: Pangaea Gondwana and Laurasia were the two halves it later split into.

21. Roughly what share of Earth's surface is covered by water?

    Answer: About 71 percent Fresh water is under 3 percent of that total, and most of it is locked in ice.

22. Which chemical symbol represents sodium?

    Answer: Na It comes from natrium, the Latin name for soda.

23. Which gas is given off when an acid reacts with a metal such as zinc?

    Answer: Hydrogen The classic test is a lit splint, which makes the gas pop.

24. Bronze is an alloy of copper and which other metal?

    Answer: Tin Copper mixed with zinc makes brass instead.

25. Which pigment gives plants their green colour?

    Answer: Chlorophyll It absorbs red and blue light and reflects green, which is why leaves look that colour.

26. The spinal cord belongs to which body system?

    Answer: Nervous system It carries signals between brain and body and handles some reflexes without the brain at all.

27. Insulin regulates the level of what in the blood?

    Answer: Glucose Too little insulin lets blood sugar climb, the hallmark of diabetes.

28. Which colour of visible light has the shortest wavelength?

    Answer: Violet Red sits at the long end, which is why sunsets look red once the blue has been scattered away.

29. A newton is the unit of what?

    Answer: Force One newton accelerates a one-kilogram mass by one metre per second every second.

30. Which law states that every action has an equal and opposite reaction?

    Answer: Newton's third law It is why a rocket moves forward as exhaust gases are pushed backward.

31. Who first correctly described the circulation of blood, in 1628?

    Answer: William Harvey Before him it was widely believed the liver made blood that the body then used up.

32. Who developed the first successful smallpox vaccine?

    Answer: Edward Jenner He used material from cowpox sores, and the word 'vaccine' comes from vacca, Latin for cow.

33. Gregor Mendel worked out the basic laws of inheritance by breeding which plant?

    Answer: Pea plants He tracked traits like seed shape and colour across thousands of plants in a monastery garden.