All Free Everyday Science MCQs with Answers

1361. Which of the following is not a waterborne disease?

• A. Cholera
• B. Amoebiasis
• C. Typhoid
• D. Influenza

Explanation: Influenza is caused by a virus and spreads mainly through respiratory droplets, not contaminated water. Cholera, amoebiasis and typhoid are commonly transmitted through unsafe water or food.

1362. Which of the following is affected by rickets in the human body?

• A. Bones
• B. Tissues
• C. Muscles
• D. Blood

Explanation: Rickets weakens and softens developing bones because of inadequate vitamin D, calcium or phosphate. It can cause bowed legs and other skeletal deformities, rather than primarily affecting muscles or blood.

1363. Which vitamin is available to the human body through sun bathing?

• A. Vitamin A
• B. Vitamin D
• C. Vitamin K
• D. Vitamin B12

Explanation: Ultraviolet B radiation from sunlight enables the skin to produce vitamin D, which helps the body absorb calcium and maintain bones. Sunlight does not supply vitamin D directly in the same way as dietary intake.

1364. Which Organ is affected by trachoma?

• A. Liver
• B. Lungs
• C. Eyes
• D. Brain

Explanation: Trachoma is a bacterial infection of the eyes, especially the conjunctiva and cornea. Repeated infection can scar the eyelid and cornea and may cause blindness.

1365. Which of the following is not a mammal?

• A. Fish
• B. Cow
• C. Goat
• D. Whale

Explanation: Fish are not mammals because they generally breathe through gills, lay eggs and are cold-blooded. Cows, goats and whales are mammals, although whales live in water.

1366. Which is the hardest substance in the human body?

• A. Tooth enamel
• B. Skull
• C. Knee cap
• D. Rib

Explanation: Tooth enamel is the hardest substance in the human body because it contains a very high proportion of mineral crystals. Bone is strong but is less hard and more flexible than enamel.

1367. In the treatment of which disease is dialysis used?

• A. Ulcers
• B. Heart failure
• C. Kidney failure
• D. Brain tumour

Explanation: Dialysis replaces important kidney functions by removing wastes and excess fluid from the blood when the kidneys fail. It is not a treatment for ulcers, heart failure or brain tumours.

1368. What causes mumps?

• A. Fungus
• B. Bacterium
• C. Deficiency of vitamins
• D. Virus

Explanation: Mumps is caused by the mumps virus, which commonly produces painful swelling of the salivary glands near the jaw. It is therefore not caused by bacteria, fungi or vitamin deficiency.

1369. How many pairs of walking legs does a cockroach have?

• A. One
• B. Two
• C. Three
• D. Four

Explanation: A cockroach has three pairs of walking legs, one pair attached to each of its three thoracic segments. Its legs are jointed appendages characteristic of insects.

1370. Which of the following is caused by a deficiency of iron in the diet?

• A. Giotre
• B. Scurvy
• C. Anaemia
• D. Rickets

Explanation: Iron is needed to make haemoglobin, the oxygen-carrying pigment in red blood cells, so deficiency commonly causes anaemia. Scurvy results from vitamin C deficiency, while rickets is linked mainly to vitamin D deficiency.