All Free Everyday Science MCQs with Answers

711. What percentage of earth's water supply is fresh water___________?

• A. 3%
• B. 5%
• C. 21%
• D. None of these

Explanation: Only about 2.5 to 3% of Earth’s water is fresh water; most of the remainder is saline ocean water. Thus 3% is the standard rounded figure.

712. Permissible noise level at Residential area during night time is:

• A. 45 dB
• B. 55 dB
• C. 75 dB
• D. 80 dB

Explanation: The commonly cited permissible residential noise limit during nighttime is 45 dB, lower than the daytime limit because quiet is more important for sleep. Exact legal limits can vary by country and regulation.

713. An edible underground stem is?

• A. Ginger
• B. Sweet-potato
• C. Sugarcane
• D. Radish

Explanation: Ginger is an underground stem called a rhizome, with buds and scale leaves. Sweet potato and radish are modified roots, while sugarcane has an above-ground stem.

714. _________ is psychological study of values and moral principles?

• A. Axiology
• B. Sociology
• C. Idiology
• D. Criminology

Explanation: Axiology is the branch of philosophy that studies values, including ethical and moral principles. Sociology studies society, while criminology studies crime.

715. Which of these fruits develop from an inflorescence?

• A. Apple
• B. Guava
• C. Pineapple
• D. Grape

Explanation: Pineapple is a multiple fruit formed by the fusion of many flowers in an inflorescence. Apple, guava and grape develop from individual flowers, although apple is an accessory fruit.

716. The floral part that produces pollen grains is:

• A. Sepal
• B. Petal
• C. Anther
• D. Ovary

Explanation: The anther is the pollen-producing part of the stamen, the male reproductive structure of a flower. Sepals and petals protect or attract, while the ovary contains ovules.

717. Gravity setting chambers are used in industries to remove ________?

• A. NOx
• B. SOx
• C. CO
• D. Suspended particulate matter

Explanation: A gravity settling chamber slows a gas stream so that suspended solid particles settle under gravity. It is therefore used to remove suspended particulate matter, not gaseous pollutants such as NOx, SOx or CO.

718. Saffron is obtained from which among the following parts of the plant ________?

• A. Anther
• B. Stigma
• C. Stamen
• D. Pollen

Explanation: Saffron consists of the dried red stigmas of the Crocus sativus flower. The stigma is part of the female reproductive organ, while anthers and pollen belong to the male side.

719. Which one of the following clouds is found at the highest level in the atmospher?

• A. Stratus
• B. Cumulus
• C. Stratocumulus
• D. Cirrus

Explanation: Cirrus clouds are thin, wispy clouds made mostly of ice crystals and occur at the highest altitudes. Stratus, cumulus and stratocumulus clouds generally form at lower levels.

720. What would you find in a Vivarium?

• A. microorganisms
• B. Animals
• C. Humans
• D. None of these

Explanation: A vivarium is an enclosed place designed for keeping and observing living animals, often under controlled conditions. It may also contain plants, but “animals” is the best option provided.