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. What are the products of the reaction when metal carbonate reacts with an acid?
[A] Salt and Hydrogen
[B] Carbon dioxide
[C] Salt, Carbon dioxide and water
[D] Salt, Carbon dioxide and Hydrogen
Show Answer
Correct Answer: C [Salt, Carbon dioxide and water]
Notes:
All metal carbonates and hydrogen carbonates react with acids to give a corresponding salt, carbon dioxide and water. Limestone, chalk and marble are different forms of calcium carbonate.
2. Who discovered electron?
[A] J. chadwick
[B] Ernest Rutherford
[C] J.J.Thomson
[D] E.Goldstein
Show Answer
Correct Answer: C [J.J.Thomson]
Notes:
In 1897, J.J. Thomson discovered the electron by experimenting with a Crookes, or cathode ray, tube. He demonstrated that cathode rays were negatively charged.
3. Saprophytes are the organisms which depend for food on
____:
[A] Inorganic chemical compounds
[B] Living plants
[C] Living animals
[D] Dead and decaying material
Show Answer
Correct Answer: D [Dead and decaying material]
Notes:
Saprophytes are the organisms which depend for food on dead and decaying material. They secrete digestive substances into the surrounding environment and break down the organic matter into simpler substances. The nutrients thus produced are absorbed directly through the cell membranes of the organisms.
4. 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.
5. Which one of the following elements is associated with teeth disorder?
[A] Chlorine
[B] Bromine
[C] Iodine
[D] Fluorine
Show Answer
Correct Answer: D [Fluorine]
Notes:
Fluorine is the element that is associated with teeth disorder because the presence of sodium fluoride in drinking water at the level of 2ppm may cause mottled enamel in teeth, skeletal fluorosis, and may be associated with cancer and other diseases. However, topically applied fluoride (toothpaste, dental rinses) has been shown to help reduce dental caries.
6. Water of coconut is ____:
[A] Liquid nucellus
[B] Liquid endocarp
[C] Degenerated liquid endosperm
[D] Liquid mesocarp
Show Answer
Correct Answer: C [Degenerated liquid endosperm]
Notes:
Coconut water, the clear liquid inside young green coconuts (fruits of the coconut palm), is liquid endosperm. In early development, it serves as a sus pension for the endosperm of the coconut during their nuclear phase of development. It contains sugars, vitamins, minerals, proteins, free amino acids and growth promoting factors.
7. Which of the following is/are agent(s) of infection?
[A] Physical contact
[B] Water
[C] Vectors
[D] All of the above
Show Answer
Correct Answer: D [All of the above ]
Notes:
Infection is the invasion of an organism’s body tissues by disease-causing agents, their multiplication, and the reaction of host tissues to the infectious agents and the toxins they produce. Infectious diseases can be spread from one person to another, for example through contact with bodily fluids, by aerosols (through coughing and sneezing), or via a vector, for example a mosquito.
8. Which of the following cell organelle contains DNA apart from nucleus?
[A] Golgi Apparatus
[B] Mitochondria
[C] Cytoplasm
[D] Ribosome
Show Answer
Correct Answer: B [Mitochondria]
Notes:
The three organelles that contain DNA are the nucleus, mitochondria and chloroplasts. Mitochondria are unlike most organelles (with an exception of plant chloroplasts) in that they have their own set of DNA and genes that encode proteins. They are specialized structures unique to the cells of animals, plants and fungi.
9. Bile is produced by the ____:
[A] Liver
[B] Stomach
[C] Pancreas
[D] Duodenum
Show Answer
Correct Answer: A [Liver]
Notes:
Bile or gall is a bitter-tasting, dark green to yellowish brown fluid, produced by the liver aids in the process of digestion of lipids in the small intestine. In many species, bile is stored in the gall bladder and upon eating is discharged into the duodenum. Bile is a composition of the following materials: water (85%), bile salts (10%), mucus and pigments (3%), fats (1%), inorganic salts (0.7%) and cholesterol (0.3%).
10. Fat present below the skin surface in our body acts as a barrier against ____:
[A] Loss of heat from the body
[B] Loss of salt from the body
[C] Loss of essential body fluids
[D] Entry of harmful micro-organisms from the environment
Show Answer
Correct Answer: A [Loss of heat from the body]
Notes:
A layer of body fat acts as an insulator and traps heat. The subcutis is the deepest layer of skin. The subcutis, consisting of a network of collagen and fat cells, helps conserve the body’s heat and protects the body from injury by acting as a “shock absorber.