General Science Questions (MCQs) for Competitive Examinations
General Science Multiple choice questions for GK paper in SSC, NDA, CDS, UPSC, UPPSC and State PSC Examinations. These questions are part of GKToday’s 35000+ MCQs Bank Course in GKToday Android App
1. How the Cast Iron is different from Wrought Iron?
- Cast iron have higher carbon content than wrought iron
- Cast iron are more ductile compared to wrought iron
- Wrought iron is more stable, pure and stronger, compared to cast iron
Select the correct option from the codes given below:
[A] 3 Only
[B] 1 and 3 Only
[C] 2 and 3 Only
[D] 1,2 and 3
Show Answer
Correct Answer: B [ 1 and 3 Only]
Notes:
Second statement is wrong because wrought iron is more ductile compared to cast iron
2. Which of the following increases with increase of highly soluble impurities in water?
- Melting point
- Boiling point
- Surface tension
Select the correct option from codes given below:
[A] 1 & 2 Only
[B] 3 Only
[C] 2 & 3 Only
[D] 1, 2 & 3
Show Answer
Correct Answer: C [ 2 & 3 Only]
Notes:
The melting point of a pure substance is always higher than the melting point of that substance when a small amount of an impurity is present. Melting point decreases with increase of impurity in water. Increase in impurity increases the electrostatic attraction between ions and thus more energy is needed to break the bonds. The surface tension of water increases when highly soluble impurities are added to it.
3. What percentage of carbon is present in steel?
[A] 0.0 to 2.5
[B] 2.5 to 5.0
[C] 5.0 to 7.5
[D] 7.5 to 10.0
Show Answer
Correct Answer: A [0.0 to 2.5 ]
Notes:
Steel is an alloy made by combining iron and other elements, the most common of these being carbon. When carbon is used, its content in the steel is between 0.2% and 2. 1% by weight, depending on the grade. Other alloying elements sometimes used are manganese, chromium, vanadium and tungsten. Carbon and other elements act as a hardening agent, preventing dislocations in the iron atom crystal lattice from sliding past one another.
4. Membrane lipids of chillsensitive plants contain ____:
[A] Low proportion of saturated fatty acids
[B] Equal proportion of saturated and unsaturated fatty acids
[C] Low proportion of unsaturated fatty acids
[D] High proportion of unsaturated fatty acids
Show Answer
Correct Answer: D [High proportion of unsaturated fatty acids]
Notes:
The membranes of chill sensitive plants have about a 2 :1 ratio of unsaturated to saturated fatty acids. It has been seen that the proportion of unsaturated membrane fatty acids increases and the critical temperature decreases so that chill-sensitive plants are more acclimitized to low temperatures.
5. In the grass lands, trees do not replace the grasses as a part of an ecological succession because of ____:
[A] Limited sun light and paucity of nutrients
[B] Insect and fungi
[C] Water limits and fire
[D] None of the above
Show Answer
Correct Answer: C [Water limits and fire]
Notes:
Ecological succession is unidirectional progressive process of development in an ecosystem or biome. Grass ecosystems are an early stage of succession in regions where the mature ecosystems are forests. However, grass ecosystems are climax ecosystems in grassland regions, where there is not enough rainfall to support a forest. Due to limiting factors such as water scarcity and forest fire, a grassland ecosystem changes to a desert ecosystem. The ecological succession of grassland is desert.
6. Which word is common in the botanical names of trees like Ashoka, Tamarind or Coral?
[A] Terminalia
[B] Indica
[C] Salix
[D] Acacia
Show Answer
Correct Answer: B [Indica]
Notes:
Tamarind tree (Tamarindus indica), Ashoka tree (Saraca Indica), Indian Coral tree (Erythrina Indica) have ‘Indica’ common in their botanical names. In biology/taxonomy, if a species originates in India, its scientific name sometimes includes “Indica”.
7. If a healthy freshwater fish is placed in salt water, what will be the expected consequence?
[A] The fish becomes dehydrated and dies
[B] The fish becomes bloated and dies
[C] The fish suffers from fungal or bacterial disease and dies
[D] There is no observable effect on the fish provided there is sufficient food
Show Answer
Correct Answer: A [The fish becomes dehydrated and dies]
Notes:
When freshwater fish is placed in salt water, the water molecules contained in the fish’s body would pass through the cell membranes of the fish, causing the fish to lose water by osmosis. This sudden change in the molecular makeup of the fish would cause the fish to undergo severe dehydration followed by death.
8. Element that is not found in blood is ___:
[A] Copper
[B] Iron
[C] Chromium
[D] Magnesium
Show Answer
Correct Answer: C [Chromium ]
Notes:
In the blood the key minerals are iron, copper, zinc, sodium, potassium, calcium and magnesium. Minerals constitute important part of blood plasma that constitutes almost 55% of blood. In the blood, iron is found in larger amounts than any other mineral.
9. The largest invertebrate is a/an ____:
[A] Sponge
[B] Mollusc
[C] Echinoderm
[D] Arthropod
Show Answer
Correct Answer: B [Mollusc]
Notes:
The largest invertebrate is Mollusc. With over 80,000 species, molluscs form the second largest phylum of animals on Earth and range from tiny snails to giant squid and octopuses.
10. Yeast is a ____:
[A] Bacteria
[B] Fungi
[C] Algae
[D] Bryophyte
Show Answer
Correct Answer: B [Fungi]
Notes:
Yeast are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom. They are estimated to constitute 1% of all described fungal species. Yeasts, such as Candida albicans, are opportunistic pathogens and can cause infections in humans. Commercially they are widely used in production of alcohol and carbon dioxide. Hence, they are known to lay foundation of bakery and brewery industries.